Hollowfication Experiment

Tosen Kaname stood quietly there, almost blending into the night.

His eyes were slightly closed, his figure thin and gaunt. He seemed less like the dignified Fifth Seated Officer of the Ninth Division and more like a ghost wandering the Soul Society.

After Kakyō was killed by Tsunayashiro Tokinada, revenge became Tosen Kaname's sole reason for living.

"Yato."

The blind Seated Officer gave a slight bow. Without exchanging excessive pleasantries, he turned and led the way.

One addressed the other by his surname casually, while the other used an honorific.

The difference in their status was immediately apparent.

This was not simply the gap between the Third and Fifth Seated Officers. Within Aizen Sosuke's group, Uchiha Yato held a higher position than Tosen Kaname!

Even with Tosen's seniority, he could not ignore Aizen's obvious appreciation and favor toward Yato.

In the night shrouded by thick fog, aside from a few brief exchanges, the two spent most of their time traveling. Both were high-ranking Seated Officers, with astonishing speed and stamina. They soon arrived at their destination.

"This is District 31 of Northern Rukongai, Dragon Plain." Guided by his sense of Reiatsu, Tosen Kaname pointed into the distance.

"The experiment is being conducted in that mountain hollow."

"Tch. District 31 has decent security. Won't this be too conspicuous?"

"They aren't local residents. The people below specifically captured them from Kusajishi District and only brought them here after dark."

Uchiha Yato nodded and asked no further questions.

Upon entering the mountain hollow, they found more than a dozen people inside a makeshift shack. Their hands were bound behind their backs, and black cloth wrapped around their heads, covering their ears and eyes.

Tosen Kaname dug into one area of the shack and pulled out a silver case.

"Yato."

"Thanks."

Uchiha Yato accepted the items Tosen Kaname handed him: a bone breathing mask and protective goggles, both exquisitely made.

Tosen Kaname also put on his protective gear before drawing a blade from the silver case.

Swish!

The blade swept out, cutting open one person's skin.

Uchiha Yato saw it clearly. The moment the wound appeared, the Reishi in the air violently trembled and forced its way into the person's body in an irregular pattern.

It dissolved into the blood, settled in the bones, fused with the internal organs, and finally hummed deep within the soul!

"Aaaaaaah—!"

The victim began roaring. White fluid poured from his eyes, mouth, nose, and ears like tar, trying to solidify into a mask!

This was a Hollow's Reiatsu, a Hollow's mask. He was about to transform from an ordinary soul into a Hollow!

Yet at a certain critical moment in the transformation, the fluctuating Reiatsu fell still.

Pop.

Like a balloon inflated to its limit, the man suddenly vanished, completely turning into Reishi. Only his empty clothes, shoes, and socks remained behind.

Yato's Sharingan spun madly. His dynamic vision rose to a terrifying level as he wrote rapidly, recording every minute change.

"This man was a wandering swordsman from Kusajishi District, a bounty hunter." Tosen Kaname rested his blade against the empty clothes.

"His Reiatsu was at level twenty, with strong muscles and bones. After being expelled from Shin'ō Academy, he fell into a criminal path devoid of all honor."

"Sounds like you're looking for an excuse for murder, Tōsen."

"No, Yato. I am merely stating his life story, and besides..."

The blind Fifth Seated Officer's tone was calm, without the slightest ripple.

"Killing for the greater good is justice."

The Hollowfication experiment continued. Uchiha Yato simply sat down and focused on recording it.

Recording every detail of the Hollowfication process was the task Aizen Sosuke had assigned Yato. The Sharingan was particularly suited to this work.

That blade capable of turning souls into Hollows was also one of Aizen's proud creations.

It was said to be formed by compressing the souls of Soul Reapers and Hollows together, forcibly embedding the crystal deep within an Asauchi. So long as it cut the skin and touched blood, it would forcibly induce Hollowfication.

Relying on Kyoka Suigetsu, along with his heaven-defying intellect and combat power, Aizen Sosuke had already built a massive underground organization. Yet only Uchiha Yato and Tosen Kaname were qualified to access its core secrets.

Thus, Yato now wore many hats. He had to bury himself in the work of a Third Seated Officer while also finding time to complete Aizen's assignments.

Past midnight, Tosen Kaname finished all the experiments. He burned the clothes, shoes, and socks with flames, leaving no trace behind.

The goggles, mask, Hollowfication Blade, and experiment records were placed in the silver case and buried underground. A few hours later, someone would come to transfer them to a secure location.

Tonight's task was complete. Yato yawned and said casually, "Tōsen, we're heading back. Want to go together?"

"No, Yato. There is a prison nearby under the Ninth Division's jurisdiction. The prisoners have been restless these past few days, so I'll go take a look."

Uchiha Yato chuckled.

That was the downside of being a double agent. He had to handle both sides' work well. Without some skill, it really would be impossible.

He bid Tosen Kaname farewell and headed back the way he had come.

The fog remained thick. Scarlet Eye was still maintaining a partial Shikai state, and the Three Tomoe spun within Yato's eyes.

Along the way, he encountered scattered patrol members from the Tenth Division. However, due to the Sharingan's illusion techniques, they could see only broken stones and weeds, unable to discern Yato's true form.

At last, the youth arrived outside Black Ridge Gate, ready to enter the Seireitei.

Just then, a patrol squad happened to approach from the opposite direction. Led by a low-ranking Seated Officer, with two members flanking him, it was a standard three-man team.

As the tomoe turned, Yato strode past them.

But suddenly, he stopped.

A soft sigh drifted out from the thick fog.

"Surprised? You can clearly see me, yet your companions treat me as if I don't exist."

Yato received no response.

"Stop pretending."

A bloody light flashed in the youth's eyes. It was not the crimson of the Sharingan, but chilling killing intent!

"You control your expression well, but your pupils have been constricting the entire time. It is extremely subtle, but with these eyes of mine, I can still see it."

The squad member on the left trembled slightly, but he did not turn around. He continued following his Seated Officer outward.

Because stopping would mean exposing Uchiha Yato's disguise. Facing the genius Third Seated Officer, he knew their squad would be in grave danger.

"I'm sorry, but under these circumstances, I can't let you leave."

Yato's voice continued to drift through the night, slipping into the squad member's ears.

"Is this your Soul-Cutter Sword's ability?"

"You distort light and observe your surroundings in another way. Because there is heavy fog tonight, you have been using this ability all along."

"It happens to counter my eyes."

"It seems we are both unlucky men."

Uchiha Yato gently stroked his Soul-Cutter Sword and slowly drew it. Scarlet Eye emitted a long, melodious hum, excited for the slaughter about to unfold.

"Uchiha Yato, Third Seated Officer of the 12th Division." He assumed the purest combat stance, his expression calm.

"State your name, squad member."

Outside the Seireitei, amid the dense midnight fog, under his companions' astonished gazes, the young squad member loudly announced his name.

"I am Sasaki Kazunobu! Captain Yano, sound the alarm at once...!!!"

He spoke rapidly, and his reaction was not slow. He wanted his companions to send out the signal as quickly as possible.

But no matter how fast his voice was, it could not outrun Scarlet Eye's blade.

"Just as I thought." Uchiha Yato's tone was solemn.

"Men with 'one' in their names are all extraordinary men."

The blade flashed, its killing intent like a startled swan.

Amid the spray of blood, the battle ended in an instant.

The night remained deep.