Shinji Matou At Your Service

To be fair, starting to transmigrate into Shinji's body was not a good beginning.

Shinji, known as "Shinji Matou," was the eldest son of the magus family, the Matou family, but he was a talentless waste when it came to magecraft. Influenced by his family environment, he grew up with twisted self-esteem and vanity, a fake magus. Self-centered and often disdainful of others, in Type-Moon's "Fate/Stay Night" written by Nasu, he did not meet a good end. On one world timeline, he died, and on another, he was injured. He had a typical pitiful, detestable, and tragic character.
Undoubtedly, Shinji's unfortunate fate was self-inflicted, but the main culprit behind his twisted personality was his grandfather Zouken Matou.

Zouken Matou, known as "Bug Lord," was a twisted old monster who turned himself into a worm and lived for 500 years by continuously devouring the bodies of others as his life extension bed.

In his youth, he had grand dreams and worked tirelessly towards them. However, as time passed, he realized that achieving those dreams would require a significant amount of time, and he was running out of time. To witness his future, he resorted to turning his body into a worm, seeking longevity.

Sadly, many years eroded his soul. Eventually, he forgot his initial dreams and became a monstrous being, who would stop at nothing to achieve immortality. He also became a shadow that loomed the Matou family for 200 years and the mastermind behind much of the darkness in Fuyuki City, where the Matou family resided.

As a transmigrator and a devoted fan of Type-Moon works, Shinji knew very well that as long as Zouken was alive, there would be no future for the Matou family. The worldline would eventually become one of the three depicted by Nasu, and everyone would be bound by his five-century-old obsession, sinking deeper into the dark vortex.

To obtain a bright future, the Bug Lord must die. He must be completely and utterly erased from this world, leaving no trace behind.

However, how can a great magus, especially one known for his longevity and expertise in life extension, be killed by a six-year-old child with an adult soul? If Shinji were still an ordinary person like in the original work, the newly born Shinji would have only one choice: to leave home like his uncle Matou Kariya, live in hiding, and lead a peaceful life.

Fortunately, when there are losses, there are also gains. Fate gave him a terrible start, but it also gave him the possibility of breaking free of that fate. It was this possibility that ultimately led Shinji to stand before Zouken and deliver a decisive blow, cutting through the darkness and paving the way for the future.

Zouken's head split in half, then quickly turned into a stone sculpture before crumbling into dust.

A vast and cold mist emanated from the fragments of Zouken's body drifting and floating toward the outside of the basement. The human body is nothing more than a shell that can be replaced at any time. This mist was formed by the soul, which was key to killing him.

Just before the mist floated out of the basement, Shinji produced an inconspicuous cloth bag and untied its fastening.
"If the Mystic Eyes of Pertrification does not affect spiritual entities, then..."

The cloth bag opened, and an invisible force swept through the petrified basement, drawing the mist towards it, which had no resistance, and sucked it into the bag.
"...I have no choice but to use it. This bag, designed to contain the heads of monsters, will serve its purpose in sealing your abnormal soul."

Shinji fastened the bag again, carefully stowed it away, and gently patted Sakura on the shoulder.

Sakura put down her hands covering her ears and opened her gem-like eyes.

Shinji's smile remained the same as when they first met. "It's over. Let's go upstairs and have a good sleep. Tomorrow will be another beautiful day."

Sakura did not answer, but she watched him silently.
"What's wrong?" Shinji spoke softly.

"Big brother's face got blood on it." Sakura reached out her hand, wanting to wipe away the stains from Shinji's face.
Shinji took a step back and shook his head. "Don't touch it, it's dirty."

"It's not dirty. Big brother is not dirty at all." Sakura summoned the courage from somewhere and took a step forward, forcefully wiping away the bloodstains from Shinji's face, not caring at all that her hand was now stained with blood.

"Silly girl." Shinji ruffled Sakura's hair. "Let's go, big brother will take you back to your room."

"Okay." Sakura grabbed onto the hem of Shinji's clothes, and together they left this basement that brought her nightmarish memories but no longer held as much fear.

As their footsteps faded away, an inconspicuous brown-flying insect flew out from the corner where Sakura was hidden. The two pairs of compound eyes looked in the direction the siblings had left, revealing hints of satisfaction and mockery.

A hoarse, deep voice echoed through the void: "Still too naive, my grandson. Never underestimate the survival ability of an old man. Hehe, your existence, similar to mine, is more suitable to be my successor than that waste."

That is the voice of Zouken, the old magus who should have been annihilated by Shinji's thunderous attack but is still alive.

This was expected.

The Zouken that was defeated earlier was merely a collective of insects.

The true body of Zouken, the vessel that keeps his soul in this world, is sleeping in the deepest part of the mansion within the insect nest that humans cannot reach.

Even if one possesses the Mystic Eyes of Death Perception, capable of killing the immortal, or the magical bag used to seal monsters, Zouken cannot be eradicated if the insects that serve as their true form are not defeated.

"All my limbs have been destroyed, and now I can't even generate magical energy. I should first find a suitable body outside,' Zouken murmured.

The flying insect flew along the shadows towards the door, preparing to fly out of the basement along the door frame.

However, at that moment, a milky-white hand emerged from the air, accurately grasping the flying insect carrying Zouken's last remaining soul.

"How pitiful," an ethereal voice rang out, resembling both heavenly music and the whispers of death.

"What...?"

The gaze lifted.

In the wavering gaze,

There stood a woman.

Silver hair without a trace of impurity, eyes like rubies, a delicate countenance that resembled something beyond humans, and a magnificent pure white gown.

Zouken lifted his head captivated by her presence. She resided in his distant memories, unchanging and everlasting in his heart, an existence akin to a goddess untouched by the passage of time.

Two hundred years ago, she was his comrade who pursued a great ideal and offered herself a living sacrifice.

Since that day, she had never aged and possessed the gaze he yearned for immeasurably.

"Justeaze Lizrich von Einzbern."

"Two hundred years have passed, Tohsaka Nagato is dead, and I'm left with only these remnants. Why do you refuse to die? You willingly transformed yourself into a monstrosity, going against our initial wishes, yet you still refuse to die." The voice, filled with immense nostalgia, was echoed once again. "Answer me, Matou Zouken."

Why?

Why?

Why?

Why do you not wish to die?

Every day, enduring pain, unable to bask in the sunlight, living in this inhuman manner, living in a way that is more painful than death.

Even though liberation from this pain is just within reach, you still hold onto all the suffering, gripping onto life tightly. Why is that?

I remember now.

Yes. Initially, it was intended for a noble purpose.

To grasp everything within one's hands. To understand all truths, reach uncharted realms. To transcend the limitations of the physical body and reach the soul's boundlessness.

A species called Humanity, confined by predetermined boundaries, seeks to break free from the endless spiral of the brain. All the hatred and all the pain are for the sake of healing and erasure.

—I recall it now.

When I learned about the lamentation of a world without paradise. If this world is empty, if even the creation of a physical body is not allowed, then I shall strive towards a place where it is permitted.

It is not about creating an entirely new world, but rather transforming myself, transforming the existence of humanity into something new.

That's right.

Just by lifting our heads, we can reach that universe, that end, and be re-born anew. It is a horizon that no one has ever imagined, reaching the ideal land that we cannot depict.

— For this reason.

Therefore, we sought the Holy Grail.

We seek a miracle beyond our human capabilities.

Until this is achieved, there is no reason to disappear.

No matter how many times we are defeated and how many times we realize that the physical body alone cannot reach it, as long as we are still alive, we will never give up.

— Yes, there is only one thing we dream of.

To abolish all evil in the world.

For an unattainable ideal, we wager our lives.

So, we must continue to exist.

Even after all our enemies have vanished, even though we know it is meaningless, we cannot stop seeking.

Believing that there is meaning in our existence, as long as we exist, perhaps we can cultivate someone who inherits our will.

Therefore, survival must continue.

Even if we understand that pain is endless, there is no reason for death.

Even if we want to change ourselves, we want to overcome the immature lamentations of our youth.

This is our way of survival, and it is the answer that we cannot find.

That's right.

Even if there are no rewards for the future.

This was an original desire.

This kind of pain.

Compared with the relentless pursuit of an unattainable desire, the desire to not die seems insignificant.

"Yes, that's right, Einzbern," Zouken whispered, more to himself than to the Golden Holy Woman.

"I remember now."

There were many words that Zouken did not speak, but Justeaze understood them in her heart. Because they were comrades from the beginning, comrades who sacrificed themselves to save humanity. However—

"The excessively long time has eroded your soul, even forgetting the original wish. Therefore, it is time to end it."

"Yes, it's time to end it. Our wishes, pain, and Makiri's mission—everything will come to an end here, won't it?"

Under the gaze of these eyes, Zouken becomes incredibly calm. It was not a bad thing for this endless journey, sparked by her, to be concluded.

"Will you continue to fulfill our wishes?"

"I will." Justeaze nodded solemnly.

"I see. Then I wish you success, Einzbern." Zouken closes his insect-like eyes and awaits his end.

"Farewell, Makiri Zouken." Justeaze tightened her grip and the insects turned into a pile of flesh. The soul that remained in the world through obsession lost its vessels and departed.

The shadow that loomed Fuyuki City for 200 years finally dissipated.

The Golden Holy Woman stepped out of the basement and out of the forbidden corridor of the Matou family.

At the intersection of light and shadow, a childbearing resemblance to the young Makiri Zouken leaned against the wall while waiting.

"Is it over?"

"It's over. I fulfilled my promises Now it's your turn." Justeaze looked into the boy's eyes without blinking.

"Don't worry, I will keep the promise." The boy's face lacked traces of color, but his tone was resolute. "However, even if we truly achieve the Greater Grail, I don't believe we can fulfill humanity's salvation... Besides, does humanity truly need salvation?"

"To be able or unable, it's always worth a try. That is the only remaining obsession within 'me'." Justeaze closes her eyes and is silent.

"As you wish, Your Highness, the Lady of Winter."

After saying these words, the boy seemed to lose all of his strength and collapse onto the ground.