Under the moonlight, Nanao held Hasumi Ren tightly, her shoulders trembling slightly.
After a moment, she let go and took a step back, her eyes slightly red.
Ren smiled and handed her the water canteen.
After chatting with Nanao for a while, the night deepened.
Ren checked the sky and escorted Nanao back to her dormitory.
He stood in place, watching her figure disappear behind the door.
After a long while, he withdrew his gaze and turned to leave.
A few days later, in the Fifth Division barracks.
It was late at night, and most of the squad members were already asleep.
Only the Vice-Captain's office still had its lights on.
Aizen sat at his desk, several documents spread out before him. They were personnel files.
Specifically, a list of victims for his next batch of experiments.
His gaze fell upon one of them.
Aizen lowered his head in thought, then scanned the topmost file, pondering silently.
Hasumi Ren, current Fourth Seat of the Fourth Division.
Graduated early as a fifth-year student from the Shin'o Academy. Briefly served in the Second Division before transferring to the Fourth Division.
From graduating the academy to joining the Second Division, and then transferring to the Fourth Division to become the Fourth Seat—all within half a year.
This promotion speed wasn't exactly fast, but it wasn't slow either.
After all, it wasn't unheard of for highly talented individuals to graduate and immediately become a Third or Fourth Seat.
In the Gotei 13, going from a rookie to a Fourth Seat in six months was considered excellent, but there was precedent.
Aizen continued reading. Aside from his outstanding talent in Kaido and exceptional performance in general Kido, he frequently visited the Kido Corps to study.
Other than that, there were no other eye-catching achievements.
But these were obviously not what Aizen wanted to see.
However, he hadn't come up entirely empty-handed.
A few days ago, while passing by the Fourth Division, he had activated Kyoka Suigetsu.
After masking his presence with illusions, and further concealing himself within the dense forest and Kido barriers, he followed a trail to the back mountain of the Fourth Division.
Bizarrely, he actually saw Unohana teaching Ren Zanjutsu.
At first glance, he could hardly believe his own eyes.
Unohana Retsu, personally instructing someone in swordsmanship?
In the decades since Aizen joined the Gotei 13, he had never seen such a thing.
This was somewhat beyond his expectations.
After all, in his memory, ever since Unohana became the Captain of the Fourth Division, he had never heard of her teaching anyone Zanjutsu.
Coupled with the recent movements of the noble families and the rumors surrounding the Shin'o Relief Clinic, Aizen now had a rough idea of Ren's intended role.
So he was the Vice-Captain candidate Unohana had chosen for herself.
But even so, did she really need to teach him Zanjutsu?
Just what was so special about Hasumi Ren?
As he continued to observe, Aizen gradually realized that Ren's swordsmanship was exceptionally superb.
In terms of pure technique, he was not inferior to some Captains who overly relied on their Zanpakuto abilities.
Was his talent for Zanjutsu the reason Unohana went out of her way to teach him? That would make sense...
During his observation, Aizen also discovered that the spiritual pressure Ren displayed was a solid fifth-class Reii.
Reaching Vice-Captain level spiritual pressure in half a year truly made him a genius.
But in Aizen's eyes, that was all he was.
Aizen set the file down, lost in thought.
From the information he currently possessed, there was nothing particularly special about Ren.
A young man with good talent, favored by Unohana, and taken into the Fourth Division for grooming.
Such stories were not uncommon in the Gotei 13.
But Aizen couldn't shake the feeling that something was off.
He recalled the conversation between Ren and that silver-haired youth the other night.
Those few words still lingered in his mind.
Aizen put the documents down, stood up, and walked to the window.
Outside, the night was thick.
His gaze drifted toward the Fourth Division.
That young man named Hasumi Ren should be resting in a room over there right now.
A talented young man, favored by Unohana, learning Zanjutsu from her, and steadily rising through the ranks of the Fourth Division.
It all seemed perfectly normal.
But it didn't matter.
Aizen turned around and walked back to his desk.
He picked up another document.
It was a progress report on the Hollowfication experiments.
[Subject Number] X-17 [Status] Failed, Disposed [Notes] Subject collapsed during the Hollowfication process; soul dissipated.
[Subject Number] X-18 [Status] Failed, Disposed [Notes] Subject achieved partial Hollowfication, unconscious. Soul dissipated after twenty-three minutes.
[Subject Number] X-19 [Status] Failed, Disposed [Notes] Subject achieved partial Hollowfication, unconscious. Soul dissipated after one hour.
Aizen flipped through the pages one by one.
These subjects were either souls from the Rukongai or Soul Reapers from the Gotei 13.
Their fates were largely the same: either their souls dissipated on the spot, or they lost their minds after exhibiting Hollow traits, barely surviving for a short while before their souls ultimately dissipated anyway.
So far, not a single subject had been able to stably maintain a Hollowfied state.
Fundamentally, this was likely due to their total spiritual pressure.
He had already tested some higher-ranking seated officers, but they still struggled to survive for long.
From this, Aizen deduced that the minimum spiritual pressure required to stably maintain Hollowfication was above a fifth-class Reii.
In other words, Vice-Captain level.
However, characters of this caliber in the Seireitei were few and far between, and none of them were easy targets.
To this end, Aizen had already begun drafting a list of potential experimental candidates and follow-up plans.
The first on the chopping block was the current Captain of the Fifth Division, Hirako Shinji.
Afterward, he would need to plan out more suitable personnel. Only when these Captain and Vice-Captain positions were vacant could Aizen plant his own subordinates in their place.
But right now, he had a rather radical idea.
Why not use someone for an early test run?
Hasumi Ren—a talented young man, favored by Unohana, steadily rising in the Fourth Division.
If such a person suddenly disappeared, would anyone be suspicious?
Of course they would.
Unohana was no fool.
If a subordinate she favored suddenly went missing or died, she would definitely investigate it to the bitter end.
Therefore, Aizen needed a foolproof plan without a single loophole.
Aizen set the document down, bowing his head in deep thought.
He needed to create a misdirection.
That way, even if Unohana wanted to investigate, she would only be led down a clear but entirely wrong path, never suspecting anything else.
A gleam flashed in Aizen's eyes.
He already had an idea.
A few days later, in the Fourth Division.
Ren was organizing medical supplies when a squad member ran over.
"Fourth Seat Hasumi, you have a mission!"
Ren looked up.
"It's an assistance request from the Tenth Division. They found some wounded in the Rukongai with strange injuries and need the Fourth Division to send someone for support."
Ren's brow twitched slightly.
"What are the specific arrangements?"
"Captain Unohana checked the available seated officers, and you're the only one with time right now."
Ren fell silent for a moment, then nodded.
"Understood."
Afterward, he packed his gear and led a few Fourth Division members out of the Seireitei.