In the lingering, heavy silence, Aizen stood before the deep crater, his gaze fixed on the slumped figure on the ground with a complex expression. Sora Naraku was gasping for breath, his eyes clouded with exhaustion.
At this moment, Aizen finally understood the source of the power his best friend possessed—power that did not resemble that of a Soul Reaper. On Sora Naraku's forehead, jagged fragments of bone were firmly embedded, appearing to slowly spread as a violent Spiritual Pressure saturated the air around him. Void-like darkness expanded within his pupils, turning them gold. Slowly, the light of reason was being extinguished from his eyes.
Hollowfication.
This was the erosion that made every Soul Reaper pale at the mention of its name. It was spreading at a visible rate, dragging his friend down into the abyss of primal instinct. Yet Sora seemed completely indifferent, even though he had clearly reached his limit.
"You're too slow, Sosuke."
Hearing the sound of footsteps approaching from the front, Sora Naraku lifted his head and offered his usual grin. "While you were busy setting up that Kido barrier, I already dealt with the traitor, Takeda Goki."
"But fighting a Soul Reaper of this caliber is definitely more satisfying than sparring with Old Man Yama. Remember to call me the next time something like this happens."
Aizen's eyes lowered slightly. Sunlight glinted off his flat lenses, masking the fluctuations in his gaze. His calm face remained expressionless, like a carved statue.
"Sora, rest assured."
"Though my research in this area has only just begun, given my talent, it won't be long before I develop a way to resolve Hollowfication."
"Until then... I'll have to trouble you to endure this."
Under Sora's bewildered gaze, Aizen began to softly chant a Kido incantation he had never heard before. Radiant spiritual light blossomed from his palm, condensing into a Kido spear bristling with hideous, jagged spikes.
"This is a sealing Kido of my own creation. It won't be painful."
"As for the Seireitei, I will personally explain matters to Head Captain Yamamoto."
"Do you have any last words?"
"?"
Staring at the Kido spear positioned inches away, Sora Naraku's face turned pale. "I think I can still be saved!"
Everything was going fine; why was he suddenly talking about Hollowfication and seals? He was just a bit injured and out of strength—there was no need to kill the donkey once the grinding was done, was there? If the guy really didn't want to save him, he could just let himself heal naturally.
"Sora, research into Hollowfication is still in its infancy."
Aizen sighed softly, his complex gaze lingering on the familiar figure in the crater.
"But one thing is certain: once Hollowfication begins, a Soul Reaper's soul will begin to collapse, eventually leading to a soul suicide."
"Wait!"
Seeing that Aizen wasn't joking, Sora's mind raced at a frantic speed. In a flash of desperate inspiration, he backhanded a blast of Bakudo Number 39—
[ENKOSEN]
A flat, circular shield of light appeared, reflecting his current appearance. Golden slit pupils, pitch-black sclera, and a violent aura that was hard to hide. White bone fragments were embedded in his forehead like ornaments.
'When did this happen?!'
Sora Naraku was utterly shocked. 'Was this triggered automatically because my Hollow power reached 20%?'
He stole a glance at the personal status panel only he could see. Amidst the ever-changing basic stats, his Hollow power had reached a high of 20% thanks to his relentless efforts. The biggest contributor to this growth was the Adjuchas that had appeared at the Yokota estate, Lumina Griffith.
In truth, he had already discovered during his daily training that when his Soul Reaper power was at a disadvantage, his Hollow power would manifest perfectly to complement the remaining strength. This was what Sora Naraku usually referred to as his "Second Phase."
However, he was surprised to see that as his Hollow power continued to rise, its physical manifestation seemed to have changed. Would these ornament-like bone shards eventually develop into a full Hollow mask?
Seeing Sora staring at his reflection in the Enkosen with a shifting expression, Aizen's patience finally ran out. Now was the best time for the seal; if they delayed any longer, the Hollowfication would cause irreversible erosion to the man's soul. By then, even if a cure was developed, the results would be limited.
However, Sora reacted even faster.
Sensing the danger from his side and having no time to explain, Sora immediately deactivated his Hollowfication state. In essence, he simply withdrew the spiritual pressure he had been venting.
A faint cracking sound echoed in the silence. The bone fragments growing from his forehead instantly turned to dust and vanished without a trace. The "irreversible" Hollowfication was gone in an instant.
"..."
In the dead silence, Aizen's expression stiffened. His pupils shrank as he struggled to believe what had just happened right before his eyes. At the same time, a sense of profound awkwardness began to grow in the quiet atmosphere, nearly drowning them both.
As a researcher, this was the first time he had ever seen Hollowfication that could be controlled at will. Because he had never seen it, a powerful curiosity was piqued. But the moment he remembered his own words and actions just seconds ago, he felt a sudden urge to silence everyone who knew about this incident.
As expected, nothing good ever happened when he took action with this guy.
Consequently, the look Aizen gave Sora became increasingly dangerous.
"Let me explain!"
Feeling his scalp go numb under Aizen's stare, Sora Naraku hurriedly spoke up. "My power is different from the Hollowfication you understand."
Aizen's expression remained unchanged, seemingly not listening at all. Standing at the edge of the scorched crater, he threw the Kido spear in his hand. It struck the barely-breathing Takeda Goki.
The Kido light merged into the traitor's body through his wounds, and countless chains erupted from the spear's shaft. Like a face-hugger, they instantly and completely sealed Takeda Goki.
Though there had been some turbulence, the result was correct. Following Ishikawa Sosuke and Hijikata Mine, his laboratory had gained another powerful "subject." Compared to the previous two, this one was far more valuable.
As a Captain-level Soul Reaper, Takeda Goki's endurance far exceeded that of ordinary Soul Reapers. Experiments that ordinary ones could not survive could be performed on him. Most importantly, his body contained the unique 'Qi' of Hell. This was something other Captains lacked.
But thinking about the source of these test subjects, Aizen found it difficult to maintain his hard-won composure. 'Just when did this guy start intervening in all of this?' Aizen subconsciously began to ponder.
Sora Naraku lay in the scorched crater, completely exhausted, silently waiting for his body to recover. The battle with Takeda Goki had looked like he held the upper hand throughout, but in reality, he had nearly burned through all his spiritual pressure. The final burst of Hollowfication had drained the last drop of his energy, betting everything on that one Perfect Ikkotsu.
It was absolute power obtained at the cost of spiritual pressure.
Aizen used Flash Step to appear beside Sora. He crouched down and began to apply Kaido while asking, "Explain it then. What is going on with this Hollowfication? I remember back in the Academy, you were a normal Soul Reaper."
Sora Naraku lifted his eyelids and grinned. "It has to do with Shino Prison. The first time I was stationed there, I dealt with two Adjuchas-class Great Hollows. From that moment on, I possessed a portion of Hollow power."
No one understood Aizen better than he did. Lying to his face was just asking for trouble; he couldn't hide it. But telling the absolute truth would be too sensational, so he chose bits of information that could serve as a distraction.
Aizen looked thoughtful, staring deeply at the man whose body was rapidly recovering under the Kaido. He didn't ask anything else. Judging by the subtle facial cues, Sora wasn't lying. But intuition told him Sora hadn't told the whole story either.
Then again, everyone had their secrets. This guy had already unhesitatingly shown his Hollowfication power right in front of him; what was there to quibble about? It was entirely possible Sora himself didn't understand the source of the Hollowfication.
Aizen focused on the treatment. He hadn't put much effort into learning Kaido, only understanding its basic principles. In his view, it wasn't necessary. A Soul Reaper's vitality was often linked to their spiritual pressure; as long as the spiritual pressure was stable and could be restored, the physical body could heal itself through its powerful innate regenerative abilities.
To some extent, this was very similar to the High-Speed Regeneration of a Great Hollow. But upon closer inspection, it involved different properties of the Reishi that composed them. Fundamentally, Kaido was just a method of stimulating a Soul Reaper's own recovery. When spiritual pressure was injected into the patient's body, combined with fixed medical protocols and corresponding surgical methods, even the most serious injuries could have a chance of survival.
Therefore, the amount of spiritual pressure and the degree of control over it were what truly mattered. And Aizen happened to fit both criteria perfectly. He didn't need to learn those tedious and useless medical rituals; he only needed to perfectly inject his peerless spiritual pressure into the subject's body.
Feeling his spiritual pressure gradually return, his High-Speed Regeneration kicked in once more. Tiny cracks healed at a visible rate, and Sora Naraku felt his withered body rapidly filling with power.
Soon, the two leapt out of the deep crater. Although he hadn't returned to his peak state, he was mostly fine. If another battle of the same scale occurred, he could hold his own.
Aizen glanced at the shadows in the ruins and gestured. "How do we handle that group?"
Sora followed his gaze.
Sensing someone's eyes on them, the dozens of noble family members hiding under a composite defensive Kido barrier collectively took a step back. To them, this terrifying existence who had defeated a Captain of the Gotei 13 in a head-on battle was someone they feared from the bottom of their hearts. They didn't even dare to meet his gaze. They could only huddle in the corner of the ruins, shivering.
Sora Naraku used Flash Step to appear outside the small Kido barrier and grinned at them. The crowd's faces immediately contorted, their features twitching in terror. The look on their faces—the sheer dread of being caught in the bathroom trying to skip class by your homeroom teacher—made Sora feel slightly nostalgic.
"Don't be afraid. I'm half-noble myself. For Yoruichi's sake, I won't go too far."
Although Sora's smile was kind, his expression sincere, and even his words sounded incredibly credible, it was hard to believe him after witnessing the previous battle. Consequently, when his palm pressed against the Kido barrier, the crowd reflexively retreated again, as if the person standing before them wasn't a Soul Reaper, but a natural predator they feared by instinct.
*Crack!*
The sound of shattering rang out. The Kido barrier the nobles had worked so hard to maintain was gone. Then, they clearly saw a fierce, predatory smile slowly appear on that harmless-looking face.
"So, I'll try my best to give you all a quick end."
What followed was the nobles' desperate struggle for survival. As the Moriyama family, who were supported by the Tsunayashiro, their members actually included several high-seated Soul Reaper experts whose Kido was remarkably proficient. Whether it was Incantation Abandonment, Post-Chant, or even Double Incantation, they performed them with ease. Such Kido masters were rare even within the Gotei 13.
Then, he was split in two by the "promise-keeping" Sora Naraku.
When the blood-red spiritual pressure once again filled the ruined courtyard, all the nobles involved in this incident were dead. For his efforts, Sora Naraku's spiritual pressure experience bar rose slightly. He even obtained the Kido technique "Post-Chant," though it was of no use to him.
Now, only the massive gains from Takeda Goki remained. Aizen had reminded him before they set out to avoid killing the man if possible. The laboratory lacked materials, which prevented many experiments from being conducted. Furthermore, the secrets regarding Hell had to be extracted from Takeda Goki. He was more valuable alive than dead.
Of course, it wasn't that he couldn't be killed eventually. Once his value was squeezed dry, his corpse could still be used for other experimental research.
After dealing with the noisy nobles, Aizen first performed a simple cleanup of the residual Reishi traces on site, then reinforced the Kido barrier that was teetering in the wake of the battle. The Kido barrier covering the entire mansion not only masked spiritual pressure but could also provide a disguise. In the eyes of ordinary souls and civilians, the Moriyama estate hadn't changed at all.
Combined with the fact that this place was located at the border of the town and the outer districts, it would be several days before the Gotei 13 discovered anything unusual. As for the disappearance of Squad 9 Captain Takeda Goki, while it was a major incident, he had deliberately avoided other Soul Reapers when he left. No matter how the Gotei 13 investigated, it would be impossible to link it to the two of them.
Mount Koifushi, Secret Laboratory.
The layout here hadn't changed much since the last time they visited. Aizen efficiently sealed Takeda Goki into a massive glass vat filled with green liquid. For safety, he added multiple layers of seals to the surface.
However, just as he finished, he suddenly noticed that Sora Naraku's expression was strange. His eyes were wide, staring fixedly at the ceiling as if a terrifying scene were unfolding above them.
"What are you looking at?"
Sora Naraku took a deep breath and looked at Aizen with a bizarre expression, asking in return, "You can't see it?"
Aizen looked up in confusion. The empty ceiling was pristine and white; nothing was happening.
At this moment, in Sora Naraku's vision, a dark-red vortex was spinning incessantly. A massive gate silently emerged from within. On the doors, two hideous skeletons were embedded, their slender finger bones resting on the seam of the gate.
Slowly, they pulled it open—