One-Punch DxD: NEO

Djall watched from behind as Euclid marveled at the screen.

The constant demands and shouts of one of the familiar-voice-receivers nagged his ear, complaints and questions dwindling his already short sense for patience.

[Euclid, I know I must sound redundant but I must speak my piece! What have you done?! What in the world did you unleash upon us?!]

Mordax's angry voice came out.

[Your parting gift has forced Lilith into a quarantine! The first since the great war! Some of our clansmen are infected by your gifts, and are protesting against this operation of ours!]

"...I did what I could to give even the Top Ten pause."

Euclid answered with fascination.

"Have you ever wondered why we can't just… clone the Trihexa? Like, create more of the unstoppable beast that forced God to his knees and create an unstoppable army of supreme super soldiers?"

The question inspired silence on the other side.

"I thought so. You see… the Trihexa's genetics are too unstable. It… it is the most volatile genome I have ever encountered. Every attempt to clone the creature will only give us an inferior strain of what we wanted. Like, for example, we want an unstoppable dragon creature… and it gives us a miscarried donkey without its lower jaw and half its face. Which is why we resorted to the Trihexa Cells, a more viable solution to using the treasure of a corpse. What I just dropped is basically a failed clone of the Trihexa, the original genome literally glued together by extreme means. I have absolutely no idea that it will lead to this. I mean…"

The screen showed the screaming City of Lilith choking on the clouds of the clone's remains.

Chaos ran rampant, soldiers dying with the purest despair Euclid had ever seen, so much despair.

"Honestly, this works better than I expected. If you play your cards right, you might be able to assassinate Sirzechs. I don't think even he has the power to resist this… look at the mutations, it is a literal wild primal airborne strain of the Trihexa cell, the purest reflection of forced evolution made manifest."

Euclid awed at the wondrous effects of his failed creation for it had done more than he could've hoped for in the most unexpected of ways. He wondered if this was how Rizevim felt when he accidentally made Djall.

[...Is there a cure?]

Mordax asked with a somewhat calmer tone.

"Djall, can you make a cure?" Euclid turned to Djall.

"Define 'cure.' I am not a living panacea. This isn't something you can just make me do."

Euclid then nodded, "...We can make a cure. We have the materials at least. Keep yourselves barricaded from the infected zone, and good luck finding a way to use the disease to your advantage. If there is a chance to take Sirzechs and the others out of the picture, now is that time."

Euclid then ended the transmission.

The screen still played out the chaos, dark red clouds shifting to and fro.

Within the rare gaps, the screen peeked at cancerous masses of flesh, pulsating tides of meat growing over the buildings, concrete, and glass.

"...So that thing is my… brother? Uncle?" Djall asked a difficult question Euclid did not know how to answer.

"In a sense… both."

Djall stared at the screen with a tilt of his head.

"...That thing that tried to flay your mind…" Djall paused with a thought.

"What about him?" Euclid asked with a hint of spite for the Demon.

"...Why did he save them when you abandoned them? My… brothers?"

"That's… not something I can easily answer." Euclid turned around, flinching when he saw Djall so close to him.

"It has me thinking… You say that I am special. Yet what makes them not special? Are they not born from my… mother's blood?"

"...Mother?"

"The Trihexa incubated me like a womb and the blood of this… The seeds of Christ fertilized it. That makes the first the mother and the latter the father… Did you confirm the Trihexa's gender, though?"

"Not sure… will try and confirm that later. Anyways, may I ask what is bothering you?"

"...Why do I feel nothing towards my… brothers while that… Demon did?"

Euclid stared at Djall.

"...What instigated you to ponder this frivolous topic?" Euclid asked.

"...We share the same parentage, correct? Yet I do not feel any kinship with the others. We are family by blood yet we are so far apart that we are strangers… It makes me wonder. Why did father choose me as his son when he made so many others?"

"Because you are special."

"Then why did he care?" Djall asked.

"Because… well, as obvious, family isn't bound by blood. Master Rizevim made you yet he treated you as a son more than his own children made from his blood. You shouldn't let yourself be bound by such petty notions, young master."

Djall remained silent. His contemplation was stewing, Euclid could see that.

He might have to request Rizevim for assistance in monitoring and furthering Djall's development.

Unknown to Euclid however, Djall's thoughts drifted to that one girl with drills for hair. Something about her felt…. Familiar, like he once encountered her before.

"…I'm hungry." Djall then said as his stomach growled.

"You will sit by the table and eat like a proper individual." Euclid replied as he turned back to the screen, planning to prepare the meal.

However, there was a loud absence of response behind him.

"...Young master?" He turned back around.

Djall was no longer there. It was not the first time that Djall disappeared to hunt his fill and avoiding table manners, usually engorging on familiars… mostly dragons.

Euclid sighed and summoned the messaging circle on his palm and placed it on his ear, "Young master Djall is coming home. Please hide our Dragon comrades and prepare the bait."

It had been a couple of days since the total disaster that befell the Underworld and its denizens.

The sudden arrival of the Vampire and the ancient demon tribes had made things complicated enough, then there was the appearance of Euclid Lucifuge and his so-called 'presents'.

Far in the distance high above the clouds was a floating fortress of ancient, alien make, a fusion of technological wonder and the fantastical vision of fantasy.

A flying castle on a dais, a castrum bedecked in reinforced metal and stone embossed with the same wild patterns of nature, a personal fingerprint of the demons on their culture.

While they were safe above, the citizens of Lilith were not. Despite the Strongest Man's attempt, the capital was struck, fear and panic as infectious as the disease.

Death or mutation greeted them upon first contact.

It did not matter if one held their breath, for exposure to eyes or open wounds was more than enough to claim their flesh.

Those that fell were not spared as their bodies were recycled as biomass, cancerous tides of flesh covering the buildings with small evidence of what they once were, bare vestiges of faces seen amongst the nightmarish conglomeration.

Even the Garou-blessed flora were not spared, and that did not account for the backlash in the world of politics.

Within the lab of Ajuka Astaroth, Issei stared at Tsubasa and Sona. Both were imprisoned in ice as naked as the day they were born; gelid rime permeating to their bones, halting the infection from spreading, from growing.

But not even the cold could stop this disease as their pulses, shown on the wavelength monitors, started to accelerate.

Saji and the rest of Sona's Peerage were there.

Rias and her Peerage were there.

Serafall and Sirzechs were there.

Even Michael and Gabriel, along with Asia, Irina, Xenovia and Griselda.

Everyone was looking at the two from behind military grade enchanted glass, outside the room, watching the scientists working around the two, Sona and Tsubasa further encased in a glass cube for analysis.

Azazel and Ajuka entered the observation room, forcing everyone to the mechanical slide door.

They waited for their answer.

"...As we have feared, the creature… bears remarkably similar characteristics to the Trihexa cell. My guess is that what Euclid dropped on Lilith was a clone of the creature. A failed one at that… I don't think even Euclid intended for this to happen. We're trying to create a cure and a vaccine to counter this but…" Azazel trailed.

"But…?" Sirzechs dared to ask.

Ajuka then took over, "...It's too volatile. The… Disease if you can call it that… It's the most vicious thing I've ever seen. Imagine an ever evolving and mutating virus changing from strain to strain a thousand times per second. That is what we're dealing with. It mutates and changes whatever we can concoct against it. We don't know how to counteract this."

"Why couldn't Asia's power purify this disease?" Xenovia asked.

Asia attempted to purify this disease with all of her power. With Issei's [Transfer] as well, bathing all of Lilith in her ascended light.

Yet it did not burn the disease away, it only excited the spread, accelerating the outbreak.

"Healing magic burns away most single cell organisms since a disease has not the barest resemblance of a Soul… each microorganism in this case has a Soul. A vicious one trying to live through others. In a way, it is more of a parasite than a disease, which is why Asia's power only gave it strength," Azazel answered.

"...What about Kiyome?" Rias asked.

Azazel then blinked, "Kiyome…. Ah, she has Stjarna's essence in her, which came from the Trihexa… Yes, I think that is an opportunity for us to create a vaccine. However, a cure is another matter. There is no cure for such a level of change, and too many have changed. Plus. The mutations are too fast for us to administer the cure… and the girls in there, I don't know how much longer Serafall's emergency cryostasis will last. The disease is adapting to the cold at an alarming rate."

Azazel's report did not help ease their worries.

"Azazel…" Serafall called out.

Her tone was an eerie calm. She did not add 'chan' as a suffix.

"What about the Demon Lords? Won't they do anything?" Serafall asked.

"Eistheth is willing to help, but she and her friends cannot make a cure. Only Philomath or Ermias… or even Ukoku can do it. Valqar can do it as well if he eats a piece of the Trihexa or Trihexa related genetic material."

Everyone turned to Azazel.

"...What do you mean?"

"The Baphomet… their ability is similar to the Agiel, but more internalized. They can gain the traits, and if attuned enough, abilities of the objects they consume without consequence. They can filter out the negative aspects of the powers they intake as well. Taalmara might be Valqar's… daughter but her affinity with that power isn't that strong. They are trying to vie for anything to give us a chance to save the girls."

Issei clenched his fists as he grit his teeth.

"...Where is dad right now?" Issei asked.

"With Genos out there rounding up the infected…. Or what's left of them to save." Azazel sighed.

"And the demons? Where are they and Dracula now?" Rias asked.

"In that floating fortress of theirs. Most likely either watching or arguing whether to do something or let the Devils suffer." Serafall said with a dark tone.

"...They can't just do that… Can they? I-I can ask Lord Dracula. M-Maybe he can…" Gasper spoke out, yet his tone reflected his lack of confidence in the suggestion.

"Gasper. I am sad to disagree with you. Dracula is a rare ruler that believes in the force of his actions." Sirzechs denied. "When we spoke, he demanded the heads of the Kings that allowed their servants to escape their Peerages before they became Chimera. It took Eistheth's intervention to convince him otherwise."

Serafall inhaled and turned at the heel.

"...Where are you going?" Azazel asked as Serafall stomped out of the room.

"To do whatever it takes." Serafall spoke with a grim cryptic tone before she left the observation room.

It was the first time for the children to see this side of her, the darkness behind her cheerful magical girl persona. Sona was not lying when she said that her sister would go to war if something were to happen to her.

Issei inhaled.

He was helpless in this. This was a battle that the fist could not solve… He stared at Tsubasa while the scientists were working hard, some were panicking as they gave orders to stabilize Tsubasa and prepare to inject something inside her to suppress the infection.

He wondered if his dad had to deal with something like this in his life or that the people died around him regardless of his actions. He looked up at the ceiling as his mind wandered to the girls he failed to save… the girls that decided to leave to find peace above.

Issei exhaled and closed his eyes as he resolved himself. He wanted to follow his father's path to become the strongest…

But like his mother said, it was a lonely path, and this world was different. It did not follow the same rules and the challenges were different.

"If there was a time to walk my own path… this is it." Issei decided as he opened his eyes. "Azazel. I want you to take me to those demons."

Azazel blinked as everyone gave their attention to Issei.

"...You got a plan?" Azazel asked, reading Issei's resolute mien like an open book, knowing his intent.

"Yeah. I'm going to make a play. There is one thing Ersi wants… and I think he is going to like it if I play it right." Issei said.

Azazel, Michael, Sirzechs, and Ajuka exchanged glances.

"...Will your plan work?" Griselda asked.

"...It has to," Issei said with determination.

Azazel stared for another few seconds before he nodded, "...Alright. I'll see what I can do."

But before Azazel could take action, a familiar voice called out.

"Hey, hey! I got something good for ya, Bossman!"

Black waltzed in with a small squad of clones, the white-faced black teletubbies waddled in with… a jar of some kind of diseased matter and Rover carried by the squad.

"...Rover?" Issei called out.

Rover was whimpering. He did not sound healthy.

"...Black. Rover sounds sick. Why does he sound sick?" Issei asked.

In all of his life, Issei never once saw Rover coming down with an illness. And he had never seen Rover looking so… weak.

"Yeah, good news and bad news. Bad news… Rover got the plague." Black stated.

[...EH!?]

Everyone reacted like oil catching fire, alarmed, panicked to hear that Black brought a diseased victim into the lab.

"...And here's the good news! Check out Rover. He's not one of the roving bands of flesh-hungry monsters, right? Right~?"

Everyone stared at Black as their eyes slowly trailed to Rover… understanding Black's implication.

"Oh… Ohhhh!" Azazel realized.

"Yeah, you got yourself a potential cure! Vaccine at best! We ain't exactly from here, you know?! Where we're from, people change into monsters almost every day before the GOD shit shat the fan, you know? Also, take this from me."

A trio of Blacks waddled to Azazel, presenting him a jar of something. It looked weak and diseased like a dried up pickle… in the shape of Black.

"...And this thing?" Azazel asked.

"Some of me got the plague. Shat the bad parts out so yeah, take a look at them if you want."

Ajuka blinked, "...I beg your pardon?"

"You can do that?" Azazel asked, ignoring Ajuka's confusion.

"Pffffff. This ain't something like acid, you know?" one of the Black trio scoffed. "Honestly, it is like how normal immune systems work. Take out the bad parts of me and then shit it out. Like poop."

"Ahhh… I see. But at this rate, Tsubasa and Sona might go through the transformation stage… I don't know how much longer they have before the cure is no longer viable for them." Azazel argued as he turned to the two in the ice.

"...Alright, I'll trust you on this. I'll take you to them. Let's hope that you can cross the burned bridge we can't." Azazel nodded at Issei.

Within the floating grand castle of the Demons, the Demon Lords congregated in a large hall, one side holding six that supported peace and the other supporting death with the Devils.

"This isn't what your forefathers wanted! What our ancestors wanted, to cruelly watch others die in front of them!" Eistheth cried out to Philomath.

[We reserve that right to those that sinned greatly, and they brought this upon themselves.]

Philomath argued.

"They didn't! They never asked for this!" Eistheth shouted in return.

"Their destiny is steeped deeply." Celtaka Alastor, the golden demon of destiny, spoke. "We are their only paths to salvation, only we can undo the damage the legacy of the Betrayer wrought."

"...But we cannot do it without unity." Weikel Iblis of Decay and Time, the faceless demon of death, spoke. "Without unity, we cannot decay the damage and renew the land, heal the scars. This is what you wanted, to have us, your children, to spread our lessons once more."

"We are here to also create and inspire others to achieve greatness, my elders." The white-suited demon with twelve eyes, the maker, the Lord of the Demiurge, spoke. "We are not destroyers. We are protectors."

"I implore you…." Xelar, the largest Demon of the room, the robed demon with two horns beneath his chin and holding a large chained tome.

However, before the conversation could go further, a loud crash and explosion was heard from outside, followed by a drop of temperature as cold wind flowed in.

[...The cheerful girl finally discarded her mask.]

Philomath spoke as he chuckled with amusement.

The door within their room burst open.

Rime and frost crept into the room, crystalline waters spreading and covering the organic-pattern door.

"You seem to not care that you are trespassing…" Ersi noted Serafall's intrusion.

"Don't play games with me. Your guards let me in on purpose." Serafall's tone was nearly depleted of patience.

"Heh… hahahaha. Of course, they are polite. You are now a guest. Please, take a seat in the lounge and enjoy yourself. Would you like something to drink?" Ersi gestured to the table.

He sounded so sincere it was a mockery to Serafall's ire.

"I have no time for that. Can you or can you not undo this?" Serafall demanded with dwindling patience.

"You mean you are asking if we can cure the afflicted, repair the land, and save the people?" Ermias asked, sounding as if he had no affiliation with Lilith or interest in the disaster.

"Yes!" Serafall shouted.

"We can… But we need the majority vote to do so, and there is no majority at the moment." Ermias smiled.

It was rare for Serafall to give in to her rage. Her aura escalated in intensity as frost spread from her feet, covering the immaculate blue floor.

"...Serafall Sitri." Eistheth spoke out. "Please, temper yourself. Violent impulse is not the answer. How much faith you have in your power to coerce, it will only exacerbate your position."

"I can't stand by and do nothing while my sister is dying!" Serafall snapped.

"So you're willing to risk many for the lives of the few? What happened to your pontificating for love and peace?" Ermias sniped.

"What will it take you to save Sona?" Serafall skipped to the point.

There was no sound, absence of sound, absolute silence from the Demon Lords on one half of the table.

From that silence, Serafall knew the answer.

"...I don't care how powerful you are… if it is for Sona, I will do anything." Serafall's mien contorted with a cold, murderous resolve; as cold as the ice spreading.

[Are you sure you want to do this?]

Philomath spoke in her mind.

"Let's see if Azazel boasting of your might isn't a farce."

Serafall's icy, piercing glare magnified before she swung her arm, immediately unleashing her signature Celcius Cross Trigger - bringing an Ice Age onto the entire complex.

At least, that was what she expected to unleash. One of the demon lords held her arm.

It was the monk, the one with horns sprouting out of him like a spiked mace, horn short, eyes of yin and yang, one in each.

"You know nothing of anger if you gave in this easily." The Salpsan Lord, Ukoku, shook his head with disappointment before he gently pressed his knuckle into her abdomen.

Serafall struggled to free her arm, but her magic was sealed by alien means, she could not expel the magic through the grabbed arm.

Ukoku unleashed the one-inch punch as the force exploded through her.

Serafall was not a brawler.

She leaned more towards a wizard-type combatant, and it was her tactic to avoid close quarter combat. She had embraced the pain of physical damage from Issei when he unleashed his full power.

This damage was different.

She felt as if Ukoku punched something else out of her in a way that left her… incomplete. There was no word to describe other than all of her rage and dark thoughts leaving her like the blood flying out of her lips.

No, it was more like every negative emotion was punched out of her… in a strange way.

Ukoku released her hand as she dropped to knees, coughing blood in the grass…

Grass?

Serafall looked up.

The table and chairs were still there, most of the Demon Lords seated.

Yet the space around them was different.

"The stage is set, Sitri. You let your anger control your actions, and you will pay the consequences," Ermias stated with finality.

"What did… you do to me?" A strange nausea permeated her thoughts with confusion. All of the negative emotions boiling within her were missing… all of the emotions that should be there were… restrained?

It was a strange feeling, not knowing she had something for so long until it was gone, but on a much… deeper level.

"Look behind you." Ukoku stated.

Serafall was not sure if she should entertain him, but she did…

Behind her was another Serafall, a reflection on her knees coughing blood.

Yet this one looked different. She was clad in her usual magical girl outfit, but instead of pink, her attire was a contrasting pitch black, radiated with such dark miasma and vile cursed energy. When she made eye contact with Serafall, there was a chill in her spine, a reflexive thought to look away from it.

"Your Yin is now externalized. Show her what she is." Ukoku stated as he returned to his seat, joining Ermias' side.

"...What is this farce?" Serafall demanded calmly with lots of confusion from her own part.

The dark Serafall then giggled with a haunting tune, a mockery of the cheerful tone she used, despite her teeth and lips caked in blood.

"...Oh, I am free! You have no idea how much I loathe you. Oh, how I can finally vent out everything the proper way… you bitch," Serafall's giggling smile fell, now a cold, stoic mien.

"...Ukoku tore the Yin from your Yang." Eistheth sadly explained. "You are facing the darkest side within you. The one you are seeing is the embodiment of your most negative aspects."

"...What?" Serafall asked, unable to believe what she was hearing.

"Uh uh uh! Eyes over here, miss cutesy! You always played the disgusting magical girl act just so you can run away from the ugliness of the world. You always kept me contained despite the fact that you just don't care about the people. You're only doing this to force yourself to become your sister's role model, you lil' bitch."

Serafall was taken aback and confused by the words coming out from the so-called dark side of herself, who was walking towards her while keeping the malicious grin on her pale-looking face.

"She is under Ukoku's influence." Eistheth continued. "And she allows Ukoku to do so because he brought her out. You are severely imbalanced that your own inner self is against you, Serafall… I wish you luck."

Dark Serafall unleashed a haunting, witch-like chuckle, as she aimed her black wand at her, her smile wide from cheek to cheek as the black ice congregated on her wand.

XoX

"This is your last chance if you want to go back, Ise." Sirzechs said - as he, Azazel, Michael, Gabriel and Issei were staring at the floating structure before them, "Nobody will fault you for retreating. We can think of another way."

Issei was in his subspecies Balance Breaker, his power ranger armor form as he looked up at strange structure built from the minds of

"The way back leads to a risky dead end, Lord Sirzechs. If there's anyone that can help us fix this mess, it is them. Definitely sure Dad can't do anything to fix this," Issei pointed out.

"True, but they won't do it for us. Ermias might tolerate me, but he will never do so for the Devils or Michael." Azazel remarked.

"What did Michael do to Ermias anyways? You told me he wore an archangel as his robes just to spite him. I'm pretty sure someone like those guys won't do something as fucked up without being fucked up as equally bad… Or worse," Issei asked.

"You're not wrong… Michael killed Ermias' parents." Azazel darkly answered.

Issei stared at Azazel in the eyes. He then slowly turned his head to Michael, who was not meeting his gaze.

"...The Michael you see is… much, much different compared to him during Genesis…" Azazel grimly added.

"...I was a young, zealous fool that didn't know better. I just… wanted to make Father proud. We all did…" Michael answered with shame across his face.

"He dealt the finishing blow to Ophibian and Renoa… the latter sacrificed herself to save her son." Azazel continued.

"...Shit." Issei inhaled. "Alright, alright… let's hope they are still willing to at least let me through. Let's do this."

They approached the structure, their breaths held in their chests, ready to-

"Welcome."

And then they were in the same room as the Demon Lords without warning.

"AChgw…" Issei nearly had a heart attack when the sight of the building was suddenly replaced by the twelve Demon Lords sitting around… a normal, long oval table made from some lustrous metal.

"...Did you really have to teleport us like this? Again?" Issei asked as he exhaled all of his stress out and undid his armor.

"We saw you coming the moment you exited Lilith, so yes. Michael." Ermias greeted Michael with venom. "...Sirzechs. Shouldn't you be more concerned for your Queen? After all, she is part of the sycophant bloodline, the same as her brother's."

"This is just as important. And I cannot do much from my side anymore."

Grayfia endured much of the political fallout once people learned that Grayfia was Euclid's sister. She was put on trial, then ordered into house arrest for the investigation of any possible collusion with the terrorist to placate the people's fears and temper.

Lord Lucifuge was with her as her escort, mostly as a contingency; he could not bear to see his daughter endure such unfair backlash from her brother's actions.

"You should learn to keep your people on a tighter leash, especially since they have a history of treachery."

Ermias snapped his finger. From nowhere, a body landed before Sirzechs, falling from nowhere.

Sirzechs looked stoic, but even he was taken by surprise by the absence of warning.

Everyone looked at the body… to see the bloody form of Serafall.

"She barged into our castle and demanded us to save someone she holds dear." Ermias answered. "We will remember this as an affront and will discuss ramifications later. Take her away… and our answer is no."

"Serafall!" Sirzechs and Gabriel immediately went to look over the downed devil.

Issei, Azazel and Michael immediately prepared themselves to fight.

"What did you do to her?" Issei demanded.

"She barged here by force. We politely refused her, and then she resorted to violence on us for refusing her." Ersi answered.

Issei inhaled as he calmed himself. He did not think Serafall had the capacity to do something this reckless.

"Still, did you have to go that far?" Issei asked.

"We didn't do it to her… She did it to herself." Ukoku answered.

Issei could only sigh - this is going nowhere.

"Anyway, look, I'm here to bargain." Issei said - while behind him, Sirzechs nodded to Gabriel who had retreated with the downed Serafall in her arms.

"I request to parlay. I wish for the power to restore my friends and everyone that got caught into this mess. And revive those that died." Issei carried on.

"We refuse." Ermias quickly replied.

"I'm not finished yet." Issei added, "In exchange, I am willing to go with you to your homeworld… And gamble my humanity and demonhood."

Ermias and the others turned to Issei. "...Gamble?"

[...Ah, how brazen. He is not truly ready to sacrifice his humanity, so he wants Ersi to earn the right to turn him into a Demon through a test.]

Philomath explained.

"What?" Ersi did not believe he was hearing. "...Who are you trying to save?"

"One of my girlfriends… And a few others."

"...And she isn't important enough for you to sacrifice your humanity?"

"She is."

"Yet you said differently." Ersi pointed out.

"...Heh." Issei broke into a chuckle. "Yeah, I know. But if I give it away like this, it will haunt me forever. I'm a selfish guy, you know? This isn't just about an exchange of a helpless, desperate man, this is also about fighting for my principal. I'm not sure how human I am at this point, and it might be pointless to simply defend my humanity since I lost my skin and had it replaced against my will, but there is no strength in giving in. Giving in to Demonhood… if I want to become something else, at least I want it to earn me. Besides, are you sure you want me to become a Demon this easily? You still owe me for the shit you pulled during the Diadora fiasco. Don't tell me you're that… basic not to struggle for it at least?"

A long silence descended upon the Demon Lords, stunned by Issei's answer. Even Sirzechs, Azazel, and Michael were in disbelief by Issei's response.

"...AHAHAHAHAHAHAHAHAHAHA!"

Valqar boomed with laughter after a long silence. It was the first time Sirzechs heard the menacing demon laugh with such mirth.

"So you are aware that you aren't speaking with the average ilk. Yes, you are correct. There is no strength in surrender, nor is there freedom. Your soul speaks true in your defiance, and it is against our way if one with such… principle throws them away so… casually. The Son of the Awakened One - Issei Hyoudou, has my support."

"Ufufufu… not bad, young one. He also has my support." Eistheth chimed in.

"Ku hu hu hu hu hu hu…. Hahahahaha!" Ersi broke into laughter. "How absurd to demand something like this from the ones that can potentially save all those you loved… Such arrogance. If I were a mere mortal concerned only for our gains and without principle beyond soulless capitalism, you would've returned just to watch them die, utterly broken and robbed of spirit. Yet, you are correct. A part of me wants to earn the chance to turn you. I already settled all debts with you the moment I left you guidance on yourself, but this… this is one debt I want to repay personally. There is one way that we can settle this within such a short time. If you lose, you will become a Demon and cut off all ties with the Devils."

Issei narrowed his eyes at Ersi.

"...And if you win - not only will we help you and your friends, you will learn more about yourself than ever and have your wish granted... And you will come to Kthon regardless. Do you accept these terms?" Ersi offered.

"No strings attached?" Issei asked.

"No strings, physical, and metaphorical. We are not conniving monstrous entities from fiction by nature. We can act the part by choice, but that's it." Ersi chuckled.

"...Good." Issei sighed with relief, not wanting a loophole disaster scenario.

The Mastema then turned to the master of Yin and Yang, "...Ukoku, if you would?"

Ukoku nodded, then Ermias snapped his finger - transporting them into a spacious dome within the compound.

When Issei and the other guests were still looking around at the new place, Ukoku had closed the distance between him and the boy.

"At ease, Issei Hyoudou." Ukoku placated when Issei's body tensed at the proximity.

Ukoku then pressed his palm on Issei's abdomen.

"I did not jest when I said Serafall did it to herself." Ukoku informed as his palm twisted, four fingers now ready to stab into his flesh. "Allow me to show you."

Ukoku Salpsan plunged his hand into Issei's abdomen.

Issei grimaced as he felt… something inside him being grabbed, something… he was not sure what the Demon was grabbing inside him. It was not his… soul? It felt like it had some relation with his soul, but there was something off.

Then Ukoku yanked it out and threw it behind him, the thing rolling across the floor before he somersaulted to his feet.

Azazel, Sirzechs, and Michael stared at the new entity. His skin was paler than that of Issei's, his eyes were demonic red… There were some horns growing from his hair, a dark, demonic reflection of the boy known as Issei Hyoudou.

Issei stared at his… warped doppelganger… he felt something missing inside him. It was hard to describe this form of… emptiness and longing when he stared at his doppelganger.

"...What did you do to me?" Issei asked, his eyes bouncing back and forth between the Demon Lord and his Doppelganger.

"...As I've told Serafall, Ukoku tore the Yin from your Yang." Eistheth spoke from the sidelines, standing with the other Demon Lords. "You are facing the dark side of yourself deep within. He is under Ukoku's influence to test you, though…"

The Yin of Issei Hyoudou growled with palpable animosity at the original with demonic malice.

"He also has all of the demonic powers you received from Ersi. He has yet to adapt to it enough for conversation. You… still have your power as the Red Dragon Emperor. A fitting theme considering the dominant political culture of light and darkness. This is a side of you that most in this current world never faced." Ukoku continued as he stepped away. "You will learn more about yourself in this exchange, hear the voice that whispers in its crispest clarity. Let's see if you pass this test."

"Holy shit…" Issei could not believe what he was hearing.

The Demon Lords actually pulled the Light Side vs Dark Side trope into reality before his very eyes. Issei watched many anime and western interpretations of such internal conflict.

AAAAAAAAAAAAAAARRRRRRRRRRGGGGGGGGGGGHHHHHHHHHHHH!

With a mighty bellow, Dark Issei turned into his demonic form. Issei smiled a little when he saw his dark side turning into a darker version of the demonic form he once used against Serafall.

The Demonic version of Issei Hyoudou then put up his stance - a more feral version of the Explosive Heart Release Fist, warped with demonic aggression and ire.

In response, Issei also equipped his Balance Breaker and enterer the Water Stream stance.

"...Whoa." Azazel and the others were overwhelmed by the sheer malice of Dark Issei's aura. They did not think that Issei was holding this much anger within.

Though they do not know the source.

"...Are we really doing this?" Issei asked with a narrowed look.

Dark Issei simply growled demonically before he summoned norse lightning in each hand along with countless light spears around him. These light spears feel eerily similar to Kokabiel's wavelength.

Issei knew a challenge when he saw it. Without another word, both combatants then moved.

"KYAHAHAHAHAHAHAHAHAHAHA!"

Dark Serafall sounded more witch-like the more she indulged in her mania.

The grassy plains turned into a infernal frozen wasteland as the two magical girls fought in a war of spells.

The area around the Demons were unaffected, a circle of paradise within the ravaged land, grass still green and untouched by the two extreme temperatures.

A stray block of ice flew their way only to disintegrate before it reached them, turning to nothingness as the Demon Lords watched, some watching with sadness and dismay.

"What's wrong, o' powerful magical girl?! Can't keep up?!" Dark Serafall smiled from ear to ear as she unleashed a wild combination of fire and ice at Serafall.

The skies turned into an ocean of steam and storms, a storm brewing in the cyclone of heat and cold, lightning starting to flash and thunder booming the skies while pink and black danced within the self-made clouds.

Dark Serafall unleashed a hailstorm of icy blades, formed not from cold, but extreme heat and compression at high speeds.

Serafall formed a magical barrier, but the hot ice sliced through it and cut her cheek with ease, forcing her to flee through the steam-clouds.

Her dark self was more vicious in her application of spells, corrupted with the intent to kill and inflict violence.

Serafall gazed at the Demon Lords, specifically the one known as Ukoku.

"Eistheth! How do I defeat myself?!" Serafall cried out.

"No cheating!" Dark Serafall screeched as she fired high speed bullets of compressed ice, sniping more of her pink uniform with astounding accuracy.

"She is not allowed to say." Ermias answered. "You came with intent to coerce another party with violence."

Eistheth looked down with sadness as Serafall continued evading her bullets.

"Then tell me why does she hate me?! She is me, right?!"

"She is the version of you that you suppressed, that you refuse to acknowledge for too long." Ukoku answered as Serafall stopped above the Demon Lords.

"She is against you because you bottled your negative emotions for so long, the truth you kept buried long enough to have forgotten about it."

"Yep!" Dark Serafall confirmed with a wild smile.

Dark Serafall unleashed another hailstorm of piercing ice at Serafall.

Serafall grimaced as she flew away. However, the ice that was about to land on the Demon Lords struck an unseen barrier.

The projectiles bounced towards her direction to her shock, piercing through her and drew blood.

"This is not a test, Serafall." Ermias reminded her. "This is your penance."

Knowing that Ermias deflected the projectiles to her, Serafall glared at the Demon Overlord before she noticed the spike of energy.

"Too late!" Dark Serafall laughed as she threw her wand forward, unleashing her signature move, her own Celcius Cross Trigger.

Half of the plains terraformed into a wasteland of black, cursed ice, Serafall imprisoned in a dark glacier.

She could feel the cursed properties seeping into her skin, her arms and legs bound in frost, her face remained unfrozen.

Her wounds were even frozen shut, the cold hardening most of her fluids and moisture into rime.

When Serafall looked up, she saw her doppelganger looking down on her, grinning at her.

Dark Serafall held up Serafall's chin.

"...How did Sona keep up with your shit every single day? Actually, how can you stand to care like this?"

XoX

Serafall then woke up with a startled gasp. Her body shot up from the bed, and the first thing she recognized after some frantic looking around was a familiar looking infirmary room.

The aroma of scented air fresheners and the hospital white theme was familiar… She looked down and saw her tattered clothes had been replaced with a clean hospital gown.

The memory of her battle against… herself was still fresh in her mind.

You only care about love and peace because of Sona! You never cared about the Underworld or your self-proclaimed love! You never cared about them! You don't care about anything, you massive bitch!

Those were the words that her dark self shrieked into her face - causing Serafall to grimace as she ran her hand on her face. Then, she heard the door being opened, revealing a certain Seraph carrying a tray of sandwich and glass of water.

"...Serafall, you're awake!"

"...Gabriel?" Serafall was surprised to see the Archangel as Gabriel ran towards Serafall and placed the tray down on Serafall's stomach.

"Are you alright?! Is there anything you need?! Did they do something terrible to you?!" Gabriel asked while looking over Serafall's body like a doting mother.

"Err, um… Get off first, will you?!" Serafall replied as she shoved Gabriel away from herself.

Gabriel looked shocked to see Serafall's outburst. Serafall quickly absorbed her short-tempered outburst.

"...S-Sorry." Serafall replied with a dejected tone, looking down on her plate.

"...I… if you want me to leave-"

"No." Serafall shook her head, "It's just… I don't know how to explain myself. They…"

"Please. You may take all the time you need to collect yourself." Gabriel nodded at her with a calm smile on her face.

"...Alright… they…"

Serafall explained what happened when she invaded the Demon Lords' fortress. It was more like they let her in since none of their soldiers intervened when she marched through the front door.

She confronted them with her demands.

They did not comply… She had enough of them and decided to use force.

Only to find out that it was a mistake when one of them tore out her darkness, literally. Then they made her fight against herself in the most literal sense.

"My word… How did they pull such a feat…?" Gabriel listened as Serafall continued narrating how the Demon Lords watched from the sidelines.

"...I don't know." Serafall shook her head. "I honestly don't know. Wish Magic, Biomancy, gaining abilities through eating, I… and this absurd curse… this doesn't belong to any schools of magic I know. And I even pestered Ajuka about this, and he can't figure it out. They… before I passed out, my dark self whispered to me…"

You won't keep me here for much longer.

Serafall could not bring herself to say it. She looked down at her hands. For a moment, she saw the pale skin of her dark doppelganger before her normal skin color returned.

She could feel it. Her love for being a magical girl… she began to question it herself..

Her family. Her Peerage. When she tried to recall the bonds she made…

She felt emptiness.

Apathy.

The dark negative emotions she once felt during the Civil War and afterwards, the memories of the time before she decided to become magical girl Leviatan.

"...I'm scared…" Serafall was truly terrified. "I… I just wanted to save my sister… and they… I don't know what they did to me. I'm not sure if I am still myself anymore."

Gabriel could only stare at Serafall without anything she could say to advise or comfort her. However, the Seraph blinked, noticing that the room - not even the building outside their room had been in fact, too quiet.

"Whew…." Outside was a voice followed by a slow clap, "Gotta say, didn't expect them to be this scary. I mean…"

Walking into the room, a man wearing a Japanese school uniform entered.

Gabriel widened her eyes when she saw the golden spear resting on his shoulder while he was still clapping the dust off his hands.

"Being able to mutate others and make others fight themselves. Psychic powers and warping reality with a wish… definitely out-of-the box magic. So damn creative."

"You…!"

Gabriel immediately took out her weapon. It was a golden Trishula, chakram rings dangling from the bladed tips.

The spear of Shiva, one of the gifts Indra gave to Saitama, Gabriel, and Crom Cruach.

"Hey, now." Cao Cao raised his hands. "I'm not here to fight. Well, if I can help it, to be precise. Besides, I'm not alone, and guess who's here with me?"

Gabriel quirked a brow.

She froze when she felt a familiar presence. She slowly craned her head to Serafall…

Garou was standing beside her bed. Serafall's eyes were glued to Garou's demonic frame, the man that nearly destroyed the Underworld, the man that blessed and renewed it into what it was today.

The moment Garou was here, they knew that they were helpless.

"Yeah, you're at checkmate. That spear you got from Shiva can't do anything to the guy that once kept up with Saitama in a fight. Besides, aren't you interested in hearing the ultimate plan of the Demon Lords that want to genocide you Devils?"

Serafall turned her attention from Garou to Cao Cao, "...What did you do to the staff outside?"

The 'hero' simply gave a small scoff while smirking, "I had Garou accelerate the time in this room. We're moving so fast that time is practically stopped outside. Nobody's life is in danger if that's what you're worrying about."

"...Are you serious?" Serafall turned to Garou.

"Alichino gave him the knowledge of every power he witnessed in the Christian Wars. This is the magic of the Agares at work, Top Ten level and beyond." Cao Cao explained as the Devil and Angel stared at the human then turned to Garou.

Gabriel stared at Garou. He was here… in front of her eyes, forced to do terrible things against his will… And she could not do anything about it; she grit her teeth.

Cao Cao blinked when he saw her wings turning black for a moment there.

"...Very well."

She sounded as if she strained her throat to say those words.

"Oh, one more thing. If you want to hear what I have to say, swear that you don't go anywhere near that one Demon Lord that looks like Cthulu. Or the Overlord. Indra said he can read your minds."

Serafall and Gabriel gave Cao Cao their full attention.

"Yep. Indra is still working with us, surprise surprise. We're his only eyes and ears on the enemy side, so he likes to keep his options available at all times. Anyways, you're thinking that you can protect yourself. That one Devil Pillar Clan, uh, Paimon, I think, can read minds as well, but let's face it, they're not worth mentioning. This Demon Lord can go deeper through whatever protection you have in your head or on your person. If you want protection, we'll, I can give it to ya."

"...What is your angle?" Serafall scowled at Cao Cao.

She knew as a politician and diplomat that someone like Cao Cao wouldn't do this for free, not without any hidden motives.

"Lord Indra's big game involves everyone. He convinced the Demons that they need you to survive the encounter with GOD, but the Demons decided to loophole that. We can tell you… in exchange for some hush-hush on your side. Like not telling Saitama or anyone else about this."

"Why shouldn't we? We both know that he can defeat GOD." Serafall pointed out.

"After what happened last time, GOD knows more than to fight him head on. The moment he sees Saitama, he will retreat to who knows where. You've seen what GOD can do in hiding, haven't you? The cults, the terrorist uprisings, your Church is being put to the absolute test while GOD uses the Biblical God's blunders against us. If that is what he can do in hiding, imagine the damage he can do if he gets involved personally. Without Saitama to save our rears."

Serafall and Gabriel exchanged glances, still not sure of what to make of Cao Cao's intention.

"...In fact, I will sweeten the deal." Cao Cao pointed at Garou, "We all know what Garou can do. The Overlord may be able to grant wishes, but even he can't pull off what Garou did here. So… you want to bet that this guy can undo whatever Euclid pulled off?"

"What?" Serafall couldn't believe what he was saying. "...Okay, seriously, why are you doing this? Didn't you join the Khaos Brigade because you want to wage war against the Supernatural for… human supremacy if what I read about you from Azazel's report is true? I know what you people did."

Serafall did not dally after the Hero Faction's personal visit to her domain. She investigated the strings of activities of the Hero Faction… there was more terrorism than heroic deeds in their record.

"I just feel like helping here, though my reason is for me to know and for you to find out. And… Well, things have changed." Cao Cao's smirk fell. "Let's just say that after giving some considerable thought when we… hit some setbacks, we decided to improvise. Besides, Indra is going all out. Like, very all out. You may think he is casual and easy going in public, but when he is serious, he is serious."

"Then what is his game here?" Serafall demanded.

"Oh, he contacted the Demons early to convince them to work with the Devils for the sake of our world. The goal here is to have the Demons and Devils rebuild the bridge that Lucifer burned down and unleash the full potential within us, humans, Devils, Angels even. But the older Demons believe that they don't… need your compliance and will to do so."

"...What do you mean?" Gabriel asked.

"The Demon Lords are no fools. But some of them are selfish and too devious. Ersi proposed a plan as an alternative to settle old debts. The Mastema plans to enslave the souls of every Devil into the war effort for their world as an alternative."

Gabriel and Serafall were overwhelmed.

The level of unhinged cruelty of that plan was…

"That's outrageous!" Serafall got up from bed. "They just… they can't just… why?! What could bring them to just…?!"

"...A long time ago, during the Great War, there were some Demons that vied for peace." Cao Cao explained. "During a rare few moments… some of the Demons snuck into our world and tried to negotiate for peace. With God… sometimes Satan. Things did not end well. Three times, young demons snuck to earth. They were burned at the stake by the inquisition by the direct order or God, thinking they were spies."

Serafall and Gabriel listened.

"The second time, Lucifer caught them and tortured them for information… he tried to blackmail the Demons into undoing the curse. It did not go well. A few of them were like sons and daughters to Ersi. They killed themselves out of guilt, to not let Lucifer use them anymore."

Gabriel cupped her mouth.

"The third time also involved Lucifer. He harvested their blood, their organs, to find out if he could forge a cure for the curse out of desperation. It is a long, long war with too many years for the two to see how many lines they can cross… I think the older war veterans just stopped caring for the Devils…. And this is just the tip of the iceberg."

"Shit…" Serafall rubbed her forehead with her body hunched over on bed, before she sat back up. "...Damn it… Now I actually feel bad using the title Leviathan…" She closed her eyes and calmed herself.

"...Why does Indra want us to get along with them even though Lucifer crossed too many lines?"

"He believes that your full powers are essential. And he thinks that their alternative is too morbid even for his tastes. Anyways, now that I have your ears, keep this to yourselves if you want things to run smoothly. Saitama ain't a good player… I mean, he sucks at playing games. Even video games. Trust me, I know. It's fun watching him react though."

Serafall nearly cracked a smile when she remembered how she beat the baldy at his own game.

Oh, the faces he made were funny.

"Telling Saitama is like adding oil to the fire. Whatever Saitama comes up with, GOD will use against him. In games, Saitama will always fail… but Saitama isn't the only player in town. We are the equation GOD will never take into account because that's just how confident he is as the Final Boss. And we will make sure to capitalize on it. You get me so far?"

Serafall and Gabriel exchanged a glance.

To take down something greater than the Great Red, something Saitama failed to defeat…

It was a dangerous plan.

"...What is Indra's plan this time?" Serafall asked.

But the idea was not something they would avoid. It was actually a thrilling idea, taking down something like Saitama.

"The younger Demons are the key. The Demon Lords kept all of the newest generations under lockdown in Kthon… but two of them are here." Cao Cao explained.

"Search for the Demons Duon Mastema and Zelel Ordog. They are your best and final chances to make peace, since the old ones will listen to them more than anything else. After all… Duon is Ersi's son. And Zelel's Ermias' daughter."

"...Eh?" Serafall and Gabriel's eyes turned into dots.

"...They have kids?" Serafall uttered.

"Yeah, it's hard to figure that out. They do not look like parents at first glance, I admit." Cao Cao wryly smirked.

"...Where are they now?" Gabriel asked, with hope fluttering in her heart.

"On Earth. They are entering their rebellious phase. They are exploring the human world in disguise… It will be hard for you to pinpoint them. But at least try to do so after the Demon Lords are left to their own devices. Not even they know they're there. And, about the sweetened deal with you-know-who?" Cao Cao gestured to Garou.

"...If you are helping us this far… then… Why do you continue to treat Garou like this?" Gabriel asked.

"Er… Well…" Cao Cao actually looked a bit awkward when replying, "One… We don't know what else to do with him. I mean, Indra handed him to us and told us to make use of him without warning. We didn't enslave him in the first place, remember? Then we just rolled along with it… and then it got to this point. Two, we kind of pissed him off the last time we met face to face… when we were in a phase… And we don't want to face the wrath of the Demon God. We're just playing along until we're strong enough to survive him at least."

"...What did you do?" Serafall asked.

"We sent him to Tartaros before he could wipe us out for… attacking a village… yeah…" Cao Cao admitted.

There was an awkward silence between them.

"...Anyways, do you agree to keep this secret? It is a big game we're playing for the survival of our world, you know?" Cao Cao asked again.

So far, the deal has been good - too good, probably. However, Serafall had one more thing in mind.

"...You do know that there's nothing really stopping us from ratting you out, don't you?"

"Indeed." Cao Cao admitted. "But then again, are you really the kind of woman to go against her word? You know how much Demons respect promises. And you Devils are famous for treachery so…"

Serafall simply glared, prompting Cao Cao to raise his hands up placatingly, dropping the joke.

"Right, so here's the deal." Cao Cao began after clearing his throat, "In exchange of our assistance to repair the damage inflicted on you devils of Underworld… We want something. Something that is definitely in your kind's possession."

"What kind of something? Didn't you have enough with the Clay of Adam?" Serafall asked, scoffing.

"...The Piece of Pandora's Box."

Both women gasped at the mention.

"Pandora's Box… God's greatest mess as the Demons like to say. Forged by Hephaestus with the resources and powers of every pantheon on Earth in a grand experiment." Cao Cao grinned. "Nobody ever knew what had become of the box itself after Pandora opened it, other than what the myth foretold; but the truth was, the box was shattered in order to prevent the same tragedy from happening again… And our intel suggested that one of the pieces is somewhere in Devil territory."

The angel and devil could not believe his words. Out of all the things he could have wanted, it was one of the most iconic artifacts of ancient times, one of the most powerful.

Or still was the most powerful.

"Why do you want that? The Pandora's Box is useless. Hephaestus shattered it and removed all of its power," Gabriel asked.

"...Or so everyone thinks. There's a Demon Lord that can use Wish Magic for crying out loud, what do you expect?" Cao Cao grinned. "The box is the ultimate seal. It is one of the things that can truly defeat the Final Boss. I don't think I need to tell you what we want to do with it."

Gabriel and Serafall exchanged another glance - the former subtly shaking her head to the latter.

"...How do you want us to seal this agreement?" Serafall then turned to Cao Cao.

"Serafall!" Gabriel admonished.

"Time is running out, Gabriel." Serafall returned, "Don't make me repeat myself, I will do whatever necessary to save my sister." She then turned towards the supposed heroes. "...How do you want to seal this deal?"

Cao Cao grinned.

Back to the Demon Lords' flying castle, a raging battle was ensuing.

Issei charged forward, dragonfire propelling him forward as Dark Issei moved as fast as lightning, both clashing in a furious exchange of fists.

Water stream against water stream.

Explosive fist against explosive fist.

Divine Lightning against Divine Lightning.

Dragonfire against dragonfire.

But that was all Issei could muster against his demonic counterpart in terms of ability.

The Light Spears floating around Dark Issei poked and prodded his defenses, stabbing at his openings. The spears did not fire, only thrusted and retracted back into position to thrust again, an annoyingly effective tactic Issei once considered when he figured out he could copy Kokabiel's Light Spears.

Crimson metal grinded sparks against the organic armor of the Demon's forearm as they weaved their respective styles.

Issei was dominating his demonic counterpart in the water stream; but when the latter suddenly switched to Explosive Heart Release Fist, he broke through his original counterpart's defenses before the light spears pierced through him.

"Guhk-!" Blood choked his system as he propelled away, gaining distance from his dark-self.

Issei grimaced; both himself and his counterpart were roughly equal in terms of technique and power, but Dark Issei showed more creativity…

Issei then blinked - both of them were the same person, could he pull the same trick off?

He tried to summon the same light spears… but he could only summon one in one hand.

"Hahahahaha!" Dark Issei mocked with laughter.

Issei scowled - Now he decided to use his mouth for anything other than growling?

He tried harder to summon more light spears, but to no avail.

[Partner. The Demon said your other half inherited all of the demonic power…]

"That's… correct." Dark Issei answered the Welsh Dragon with a growling voice.

He sounded as if he was forcing the words out his throat.

[...Wait, you can hear me?]

Ddraig asked. He was supposedly speaking with Issei privately.

"We… are the same. We… are still connected. We are one and the same. I have all of the demonic power, and the magical potential that comes with demonhood. You are now the version of me before we turned."

With every word, his fluency sharpened into a crisp narrative flow.

"Finally, I got used to this. You have no idea how intense and difficult it is to center myself in the emotional storm that is my spite." With the casual raise of his arm, Dark Issei summoned spheres… of the Bael's power of destruction.

Sirzechs' jaw nearly dropped upon seeing his clan's signature power being used like this. At this rate, Issei may have the potential to become the next Demon God.

Alarmed, Issei ran with Thunderstep, lightning trailing his steps as Dark Issei threw a swerving barrage of erasure at him.

Issei grimaced as he threw the light spear at Dark Issei, but Dark Issei caught it in his hand. The light spear then exploded in a blinding flash.

Dark Issei roared, "You're using Iri's cheap trick?!"

Issei grinned as he moved in while Dark Issei was disoriented. With Thunderstep and his flame jets, he swiftly sliced through the distance between them.

But before he could close in, Dark Issei used his Norse Lightning Darth Sidious style, forcing Issei to sidestep and fly around the blinded Demon.

However, Dark Issei sniffed the air and tracked his position.

[He's using his nose to track you!]

A clever, but simple trick.

While circling Dark Issei, Issei banished his helmet and exhaled a stream of dragonfire.

Dark Issei summoned a magic barrier, the flames splashing against the protective surface as it arced over his head and splashed behind him.

The heat was masking Issei's scent, forcing a grimace from Dark Issei as he was surrounded by fire.

"Come out and face me, coward! You think you're strong?! You, who ran away from responsibility more than once?!" Dark Issei roared, his voice warped and garbled with demonic rage.

"What the hell are you even talking about?!" Issei shouted from outside the fire.

"You let those girls die to Diodora because you don't want them to hold us down! You ran away from responsibility the moment it faced you!"

The three leaders widened their eyes at Dark Issei's accusations. They now understood what this Issei represented.

Issei was in the air, stunned by where the words hurt most.

"I… you know as well as I do that we didn't ask for them!"

"Then why didn't you send them away?! You let them into our lives and half-assed it! You let them get close to us, and for what?! To have their deaths weigh on our conscience?! Mary, Zama, Amanda, Catherine, they are gone! They deserve better than to go to heaven like this!"

"You think I could just kill him back then, just like that? You know the shit we'll face if we do something that reckless!" Issei shouted back with equal rage.

"Excuses! And you!" Dark Issei turned to Sirzechs, the Satan flinching when their eyes met. "For all of your power, you are useless! You and my other self, the ARROGANCE! Thinking you can just let the enemy live and not expect them to do something about it! Thinking you can contain them! Don't think you're free from the blame!"

Azazel and Michael were overwhelmed by Dark Issei's rage.

"All this time wasted on politics, since when have you trained seriously for once?! Letting the younger generation work their asses while you sit behind doing who knows what!"

Sirzechs remained silent, unsure whether to lash back against this Issei or not. He was still overwhelmed behind that confused face, seeing all of Issei's true thoughts being spilled without the dam holding it back.

Issei could only reply by charging forward - all he had in mind was to shut his darker counterpart once and for all.

"...And back to you!"

Both sides of Issei Hyoudou clashed, demonic hands holding draconic fists at bay as they glared into each other's eyes with growing intensity.

"Sticking to them when they have clearly failed! Michael can't keep his people from being idiots! Azazel can't keep his people in check! And The Satans let their nobles do whatever they want! What is it about them that you just let them go?!"

"And then what?! Let the world tear itself apart?! You know better than that!"

"Yet they did it too late!"

[Boost!]

Issei started boosting as he pushed Dark Issei back, Dark Issei grimacing with a snarl.

"You can't Boost, can you?" Issei noted as he continued boosting himself.

He received a roar of rage as Dark Issei retaliated, but Issei overwhelmed him, using the accumulating extra power to overpower his demon.

Dark Issei threw a desperate Exploding Heart punch, but Issei deflected it back into his mirror's face using his dad's move, the one he saw Saitama use against Demon God Garou, hooking his arm around the elbow joint and deflecting the punch back towards him.

The impact resounded within the room.

The three leaders could feel the damage the dark mirror received as blood and teeth flew in the air, broken horns as his demonic head threw back.

However, Dark Issei grabbed the original's forearm.

Transfer!

Issei could not describe the level of shock within him when his copy… used Transfer to take away all of the power he accumulated.

"Heh... It worked." Dark Issei's bloody face regenerated, teeth, chitinous armor, horns, all regrown, his face now a vicious grin.

Explosion!

Then Dark Issei bashed his forehead into Issei's face. The collision rang throughout the room, an loud, smashing echo that briefly died long enough to leave a lasting impression. Issei's face nearly caved in from the impact.

"Did you forget?! We're one and the same! Still, can't believe it worked!" Dark Issei opened his mouth the moment Issei looked down.

Dark Issei then exhaled a stream of flames directly at Issei point blank, roasting him in the inferno.

"""Issei!"""

The three leaders shouted at the brutal sight.

However, Dark Issei noticed something.

A blue cone of light bypassed his flames and bathed his head in. All of the flames he exhaled was being sucked into the opened top of the wooden prison attached to the original's left gauntlet.

"The Urn!"

Dark Issei could not react when Issei blasted all of the energy the Urn of Wei Cheng absorbed back into his dark side's face.

"I still have all of the gear." Issei reminded, his face bloody and bruised, his nose caved in, yet his resolve was still burning strong.

He bashed his head back into Dark Issei's face twofold, sending his dark twin flying into the wall, covered in a cloud of dust and rubble. Dark Issei emerged from the dust roaring with rage as the two halves ran towards each other and reengaged.

There was no finesse in their fists. Each of them struck the other in the face with all of the superhuman might they could muster within them.

Dark Issei broke Issei's helmet and crimson chassis, the emerald of his armor clattering across the floor with the shards of his subspecies scale mail. Issei broke his twin's organic armor, breaking more of his horns and spines, his demonic body cracking with each and every blow they delivered to each other.

The leaders did not know how long two divided Isseis fought each other, breaking down each other's final forms.

Eventually, Issei and Dark Issei were in their base forms, Dark Issei and Issei breathing heavily, tired, bloodied and bruised by each other's fists. They exhausted each other to the point of them running on fumes.

Their battle reached its conclusion.

"I think I know what you are…" Issei spat out the blood in his lips at the side. "What should I call you? Regret? My hatred for myself? Because of my failures?"

"I… am all of that…. And more." Dark Issei pressed one side of his nose and snorted out the blood.

"I get what you mean now. We're tired of the shit we have to deal with. The shit we shouldn't be dealing with."

"...Now you get it." Dark Issei and Issei started circling each other, both never refusing to break eye contact.

"But you should know why we ended up at this point in the first place. Do you want me to feed you or something? By screwing up even more if we do what you say and cut off ties with the Three Factions?"

"The only reason we're tied to them is because Dad needs Azazel to pay the house bills."

"Are you saying this out of your own free will or because of the Demon Lord's influence?" Issei retorted.

"You finally caught onto Eistheth's tidbit." Dark Issei scoffed. "Some of it is from him, but I don't mind. He brought me out, something no amount of willpower can do. But this is a test, after all. So here's something from me. You're a coward, a biased coward. You think being human is the only way to reach dad's level because it's the one way you're the most comfortable with. Mom keeps telling you yet you refuse to listen. Dad is the way he is because he has no one back in his world. There, being a monster means to give up everything you are. Being a monster means to surrender, to give in to your weakness for power, like selling your soul to the Devil because of how pathetic you are. But not here."

The two twins stopped.

"...Things are different here. And you're afraid to let go of your humanity because you're scared you'll never reach dad's level if you do."

There was a tangible force stopping all thoughts in the room, stunning the air into absolute silence.

"You're a hypocrite. You want to reach their level, you want to keep being human, yet you rely on Ddraig. You idolize Garou more than you do to dad. You want to become something more than human yet afraid to let go of being human."

Issei grimaced, sensing some truth in his dark counterpart - Saitama, Garou, Genos, Black Sperm and even Rover; all of them stood in the realm that was still beyond him.

"...Why do you reject me? You know that at this point calling us human is pointless. The word no longer matters. We're beyond human, we're… I'm not sure if we're supposed to be the humans God once intended us to be or if we're something more at this point, but labels shouldn't define us anymore. What are you afraid of losing if you embrace this truth? You even went so far as to jeopardize Tsubasa, Sona… and everyone else that fell victim to the plague. I respect the hard way, but this is ridiculous. You know this!"

"...Dad managed to get so strong in like… three years, you know?" Issei slowly relaxed his fists, his finger unclenching as he slowly exhaled.

"We've been training our asses off for more than ten years… yet look at us." Issei waved his arms around. "We're growing stronger, yeah… but sometimes I feel like I'm living in his shadow. I know that everyone has their own pace… but still."

"And I hate you for letting this one weakness get to you."

"Yeah… I get it." Issei nodded in understanding. "...This test isn't about fighting and overwhelming each other like in the anime and movies, isn't it?"

Issei turned to the Demon Lords.

Ukoku… cracked a small smile in his direction.

"...Heh. Wow. It's a good test. It's not something outside knowledge can help, isn't it?" Issei turned to his dark twin.

"There's no point if you do. The test would lose its meaning. There is more strength and meaning in finding the answer within." Dark Issei answered.

"Are you saying this or is that the Demon Lord talking through you?" Issei asked.

"Both."

"...Alright." Issei inhaled as he spread his arms apart. "You decide."

Dark Issei blinked. "...Decide what?"

"Human or Demon. You decide what we'll be when we're one again." Issei stated.

"What? This… such disrespect! Are you that afraid of choosing for yourself?!" Dark Issei accused.

"After all of this shit I put us through, you deserve the right to choose more than I do."

Dark Issei stared at Issei. His eyes started to blink rapidly trying to process this.

"You…"

"We're one and the same, like you said. Two in one. The twin brother I never knew was there, heh." Issei smirked.

"...This is no different than surrender." Dark Issei warned.

"Surrender means having no choice. I have a choice. This isn't surrender. It's acceptance." Issei countered.

"Hooooh…. Not bad." Ermias leaned forward.

His answer stunned the three leaders with his level of mental and spiritual growth.

"...So you're letting the dark one call the shots in the end? Aren't you afraid of turning to the dark side or something like in the movies?" Dark Issei called out.

"Well, guess we'll find out. You made a choice yet, me?" Issei snarked.

Dark Issei broke into laughter at the sheer absurdity of it all.

"And I was afraid that I'll be shoved back into the dark corner where my voice will never truly reach you… Hah. Alright."

Dark Issei walked up to the original.

"You know how this works." Dark Issei slit his wrist on one of his horns and offered the hand to him.

"Really? We're doing that?" Issei scoffed as he summoned Boosted Gear and slit his wrist.

"You better not regret the outcome." Dark Issei smiled as they held each other by the wrist, their wounds touching.

Everyone watched as the two sides of the same coin - shook hands by each other forearms, before they were engulfed in a blinding light.

To be Continued…

Omake I: Issei vs Serafall Conclusion

"-ter! Big Sister!"

Serafall blinked her eyes open and she saw the eyes of her baby sister peering on her.

She felt like bells were constantly ringing in her skull, her mind still delirious from… something? It felt like a massive hangover.

"Nnnnnghhhh… what happened?" Serafall asked as she rubbed her head. "I felt like I went to a drinking contest with Saitama-chan…"

It ended up horribly in his favor and ended with her in a drunken rampage.

"Uh, what's the last thing you remember?" Sona asked.

"Hmmmm… oh. I was fighting Isami-chan."

"You turned Issei back." Sona reminded.

"Oh, right. Then he got super angry and said that he is going to unleash his inner demon on me or something… Wait, he has a second subspecies…" She slowly remembered… "But for some reason, I can't remember anything else… Did I win?" Serafall asked.

"...Uhhhh…"

"I lost, didn't I?" Serafall concluded with a deep suspire. "How did I lose? I swear I can't remember that for the life of me."

All she remembered was seeing Issei's demonic version of his power ranger armor and then she remembered the sensation of being rammed by the Underworld transdimensional train at full speed.

It was the first time she actually lost… to someone that didn't hit the twenty year mark. Honestly, her pride as a Satan was struck by that.

"Well…" Saji was the next to speak up. "He went all Demon God mode and roared a bunch of nonsense. 'You genderbending incest magical hentai hag' is his opening line."

Serafall's mind clicked. She recalled that moment, his newest form… and that something in her turned off at that moment.

"And then he, like, owned you. You put a good fight but damn, he like smashed you hard. He was super fast as hell, we couldn't see him," Tsubasa added.

"He punched you straight in the gut and you were like 'bleeeegh'!" Ruruko punched the air for emphasis.

"No, no, he used a consecutive combo finisher. There is no way he can defeat my sister that easily." Sona argued.

"No way, he definitely uppercutted her and slammed her down! Two shots! I know how he works!" Tsubasa quipped.

Sona and her Peerage started arguing on how Issei defeated Serafall.

Serafall pouted at her loss as something caught her eye. She saw a glacial wasteland in the distance, the ice age she made in the distance using her grand spell.

She remembered her using it against him in the moment but missed.

"...So what happened to Issei-chan? Where is he?"

Her question stopped them from quarreling.

"Oh… ohhh." Saji realized something. "Well, he started acting a bit funny. He gloated at first, very… show-off ish and then started swearing something about a crusade against every magical girl in the world. He looked a bit high in the moment when we tried to reach him. It's the first time we saw him talk to himself like that… and then he took off laughing about burning down your studio."

"...He's going to burn down my what?!" Serafall shouted.

How could they leave out something so important like her studio about to be burned down?!

"Oh… yeah. Crap, we weren't sure if he's serious." Saji relented. "And we were kind of scared to stop him, so…"

"NOOOOOOOOOO! How dare he!?" With shock, fear, and fury, Serafall immediately summoned a teleportation circle under her feet and vanished.

She immediately appeared near her destination, ready to put out whatever fires that Issei might-

"...Oh, hey." Saitama waved at her.

Her studio was… intact.

Lying beside Saitama's feet… Was Issei Hyoudou, his face kissing the concrete.

There was a large bump growing from his head.

"...Saitama-chan? What are you doing here?" Serafall asked with her eyes darting between father and son.

All of her worries were flushed down the drain at the ridiculous sight.

"Was, uh, walking around. Heard a commotion, so I checked it out. Didn't think it was Issei, though."

Serafall stared at Saitama for a few seconds before she nodded, "...Right." She then glanced at Issei, "Thanks, I guess."

"It's kind of funny, seeing him breathing fire and throwing threats at the building. Don't know why though…" Saitama grabbed Issei and slung him over his shoulder. "Anyways, gotta bring him back. Hopefully, Genos can explain everything here. Issei will be back to apologize."

Serafall simply waved without a word at Saitama's retreating back.

For some reason… she felt… empty?

There was a sense of anticlimactic disappointment she could not describe, like a build-up towards the climax of a movie… only to have it stolen from her.

Probably a figment of her imagination.

Now, what she should do to make Issei pay for nearly burning down her studio?

Omake II: Juiced Up

"...Come again?" Saitama asked his wife as they and everyone else were spending some family time in the living room after dinner.

"I want you to juice me up." Haruka replied, "You've trained this… Power transferring from Cleria, right? I want you to use that on me."

"Err…." Saitama glanced around before replying, "I don't think that's a good idea, hon. I mean… I'm still training and all."

"I think you can try that now, Saitama." Cleria replied - she was sipping a cup of herbal tea, while gently rubbing her pregnant belly on the couch. "Your control has been improving a lot, I think your wife can take it."

Everyone noticed that Cleria winked at Haruka, who returned with a thumbs-up.

Saitama wanted to retort to the devil, but instead he decided to go straight to the topic, "...Haruka, what do you want to do with this…. Power from me?"

"Honey, I think you already know." Haruka let out a husky purr from her inner sexual beast.

Issei - who had been trying to ignore his parents flirting in front of everyone by reading a comic book finally put the book down.

"Oh, for the love of - Dad, just get mom to your room and be done with it, please?! We're all listening here, y'know!?"

The girls were blushing - Rias, Irina, Koneko, and Asia were awkward while keeping Cleria's children distracted. Akeno, Griselda and Xenovia were looking more curious at how things would conclude. Vali looked like he wanted to simply leave the house.

Masaomi was already accustomed to the dirty talk, along with Genos and Black who were simply listening.

Saitama closed his eyes - thinking hard of his next decision. Haruka simply smirked and tip-toed so her mouth could reach his ears.

Either nobody could not hear, or chose not to hear with their enhanced hearings of what Haruka whispered to her husband - Saitama's next response was a long exhale as he took his pleased wife in a bridal carry before he quickly left the room.

"I swear, those two…" Issei grumbled, while the girls sighed in relief.

Genos then turned to Cleria, "Cleria Belial, are you sure Saitama can pull it off?"

Cleria merely shrugged, "Considering who we are talking about, I think-!?

However the whole building was suddenly caught in a tremor.

"Whoa whoa whoa!" The Blacks wobbled from the waves as Rover yelped and hid his head under the carpet.

Everyone held on for their lives, confused by the unexpected earthquake.

Then they understood the origins of this catastrophe when they heard it.

Aaaaaagh! Fu-Fuck! Yes! !YEESS! AAAAHN~!

Nearly everyone' face went beet red at the voice echoing throughout the building. Issei was the first to stand up.

"Fuck this, I'm crashing in a hotel somewhere."

"I'm behind you." Vali followed suit.

Genos, with his ever-calm and stoic expression, clapped his mechanical hands to gather everyone's attention.

"I believe it is for the best that everybody does not spend the night here. Gather your belongings and follow the evacuation protocol in a calm and orderly fashion."

While everyone began to follow Genos' instruction, Black scooted over, "...Do you think the house can survive by morning?"

Genos replied, "...The building has been constructed with state of art, quake-proof technology. It should survive those two…. Probably."

"...Huh, okay."

YES! HARDER! HARDER~!

"Mom, what's happening?" Sarah asked Cleria, confused.

"Nothing dear, we'll tell you when you're older, hahahahaha!" Cleria quickly moved her children out of the building, followed by Mr. Carp and Mr. Crab.

For those who are concerned about the gender-bending schtick, the climax of Ise vs Serafall should be the end of that... Should be.