Bleach: The Fifth Division Captain

The definition of the Soul Society is quite broad.

Beyond the Seireitei, where the Shinigami and noble families reside, the surrounding districts are divided into four large regions, corresponding to the cardinal directions.

These are the areas known as Rukongai, or the Wandering Soul Districts.

According to the Gotei 13's intelligence reports, Rukongai is further segmented into several numbered blocks.

The closer the district is to Seireitei, the better its law and order.

Conversely, the farther the district lies from the central city, the more rampant the crime—murder, arson, and lawlessness become everyday occurrences.

"Merely because they covet our swords and whatever valuables we carry, they're willing to kill strangers without hesitation."

"How pathetic. To people like them, human life holds no value at all."

"Seiya-kun, Tōsen, you're both from Rukongai yourselves, so you should understand the tragedy of such a hopeless environment."

Aizen toyed with a small, translucent crystal in his hand, his expression calm and composed.

Three ragged spirits lay motionless on the ground around him, their lifeless bodies drained of all vitality.

Seiya Arima watched as the remaining traces of their souls were drawn into the semi-transparent orb in Aizen's hand.

The swirling essence inside seemed to writhe, shadows dancing faintly within the crystal's depths.

Hōgyoku.

The origin and purpose of this mysterious artifact had just been explained to Seiya moments ago.

It held an extraordinary power, and even its latent spiritual pressure hinted at its terrifying potential.

"Fascinating... It looks like an ordinary object, yet I can sense traces of consciousness within it."

The Hōgyoku was absorbing souls.

That was the reason Aizen had chosen to venture into Rukongai tonight.

In lawless districts like these, life and death held no particular meaning.

Even if someone went missing or was never seen again, the most they would become was a statistic—a number recorded in the Soul Society's bureaucratic ledgers.

Unlike Urahara Kisuke's Hōgyoku, which was created using vast numbers of Hollows, Aizen's version was crafted from powerful souls with latent potential to become Shinigami.

In other words—

The souls of those in Rukongai with the potential to become future Shinigami.

For Aizen, killing these souls carried no emotional burden.

No—

In his view, the residents of Rukongai were essentially meaningless.

In the Thousand-Year Blood War arc of the original timeline, Kurotsuchi Mayuri ordered the extermination of 20,000 residents of Rukongai to restore balance after the Quincy eradicated a large number of Hollows.

When reporting this to Yamamoto, the old man's only response was:

"Why didn't you notify me beforehand?"

Perhaps there was an element of resignation in Yamamoto's tone—an acknowledgment that what was done could not be undone.

But ultimately, the core doctrine of the Gotei 13 had little to do with the lives of Rukongai's residents.

After two hours of prowling through Rukongai, Aizen concluded his soul-collection mission for the night.

The trio was about to head back when a series of blood-curdling screams echoed from a nearby street.

Moments later, a blood-soaked man stumbled around a corner, shrieking in terror. His left arm was missing, severed at the shoulder.

"Help me! Please, help—"

Before he could finish, a monstrous creature lunged forward.

A pale, serpent-like Hollow with a long, sinuous body pinned the man to the ground with webbed claws, then opened its grotesque maw to devour him.

The Hollow slithered forward, licking up every drop of blood and flesh, until the body was reduced to nothing.

Then it cautiously turned its head toward Seiya and the others, its yellow eyes glinting with animalistic wariness.

After a tense pause, the Hollow slowly retreated into the shadows of the surrounding trees.

Hollows invading the Soul Society was not unusual.

Even back when Seiya lived in Rukongai, he often heard stories of entire families being slaughtered by these creatures.

Hollows were especially active at night, which was why most Rukongai residents avoided venturing out after dark.

Yet, the three of them simply stood there and watched as the Hollow slithered away, making no move to intervene.

Why?

Because of Aizen's prior instructions.

"Exterminating Hollows causing havoc in Rukongai is the responsibility of Seireitei's Shinigami. But that's not why we're here. Let's pretend we didn't see anything."

"In most cases, Hollow extermination missions start with an investigation to determine the area of activity. Only after confirmation would the Thirteenth Division dispatch a team to eliminate the threat."

It wasn't just about following protocol—it was about minimizing exposure.

Aizen couldn't be certain whether any Shinigami had already taken notice of the Hollow's activity in the area.

If they stepped in recklessly and were discovered, it would only increase their chances of getting caught.

Besides...

"The weak are consumed by the strong. Death is simply another part of the natural cycle. We're merely spectators."

Aizen's cold, detached statement left no room for doubt.

It was clear that, to him, the lives of Rukongai's residents held as little significance as they did to Yamamoto and the other captains.

Seiya also noticed the subtle shift in Aizen's gaze when he observed the Hollow.

Considering what would happen in the future, it was safe to assume that Aizen had already begun contemplating experiments to merge Hollow powers with Shinigami abilities.

After completing their mission, Aizen led the group back into Seireitei.

"That's it for today. Seiya-kun, Tōsen—three days from now, same time and place."

"Of course, if anything comes up, I'll contact you in advance."

The three-day cycle wasn't just for convenience.

As the newly appointed vice-captain of the Fifth Division, Aizen was already stretched thin with his duties.

Additionally...

"Captain Hirako seems to have some... reservations about me. He's been keeping a close watch lately. To avoid suspicion, try to minimize contact with me during regular hours."

So Shinji Hirako was already growing wary of Aizen.

Things might seem unchanged on the surface, but beneath it, countless events were quietly unfolding, hurtling toward an inevitable conclusion.

There was a growing sense of unease.

But for now, Seiya knew his priority was to grow stronger.

Without strength, he couldn't hope to withstand the dangers ahead.

Three days later—

Another night of training and feeding the Hōgyoku.

Just as Seiya thought the session was over, Aizen smiled faintly and proposed something unexpected.

"Hmm, this place is remote enough... Let's do it here."

"...Huh? Do what?"

Aizen's eyes gleamed as he turned to Seiya.

"As a reward for enduring two full sessions, I'll offer you a special lesson regarding your Zanpakutō."

"So..."

"Release your Zanpakutō, Seiya-kun."