A/N: Currently hovering between the rank 10 and 11. If maintain the top 10 until Sunday reset, I'll publish 3 bonus chapters.
***
[Loading 'Evolution Database' function.]
[Soul: The purest form of a being.
—Current path of evolution (Hollow): Hollows are souls who materialize their Inner Heart through the corruption of sins. They lose their minds to raw instincts and animalistic desires. Hollows have existed since primordial times.
Soul (Base form) -> Base Hollow (Materialization of Inner Heart and domination by raw instincts) (Achieved) -> Gillian (Fusion with Souls of similar affinity) (Achieved) -> Adjuchas (Formation of a new consciousness capable of dominating raw instincts) (Achieved) -> Vasto Lorde (Partial harmony of raw instincts with consciousness) (Achieved)
Potential Evolutions in this path: Arrancar (???) -> ??? (???)]
—Alternative path of soul evolution (Shinigami): Souls who manifest their Inner Heart by external means…
Soul (Base form) -> ??? (???) -> ??? (???) -> ??? (???)]
[Human: A soul residing in a vessel of Kishi to interact with the World of Living.
—Potential path of human evolution (Quincy): ??
Human (Base) (Achieved) -> Quincy (???) -> ???
—Alternate potential path of human evolution (Fullbringer): ??
*Evolution Database will be constantly updated with your knowledge.
The wealth of information overwhelmed Kazuya. As he sifted through the options, he noticed an asterisk at the end, accompanied by an explanation for the numerous question marks scattered throughout the list. The note made it apparent that the status only reflected his current knowledge. Any gaps in his knowledge or memory resulted in the mysterious question marks.
'When did I achieve Adjuchas-Class?'
The (Achieved) marks whispered the possibility that he began as a humble Hollow, with those memories vanishing like a mirage or being cast aside like broken toys when he transformed into a Vasto Lorde.
'Whatever. They don't matter.'
He narrowed his eyes at the tick mark available in front of every potential evolution path. He could regress to a previous evolution and even try out the Quincy path. It was a convoluted approach compared to his desired ability to switch races at will. Well, he wasn't going to complain about a power with plenty of potential down the line.
This also implied,
'I can become a Shinigami.'
The thought made him excited. Most of the Bleach story took place in the Soul Society, and most of the intriguing characters lived there. Compared to events of the Soul Society, Hueco Mundo felt stupidly plain.
'I wanna meet Mama Unohana, Yoruichi, Rangiku… Rukia too.'
Pushing his personal desires aside, he knew staying as a Vasto Lorde in Hueco Mundo would attract Aizen's predatory gaze. Aizen would scout for powerful Hollows to fill the ranks of his Espada. Rather than waiting, Kazuya felt compelled to go out there and learn about the current events. Going to the Soul Society would also mean having a chance to evolve his Shinigami form and wield a Zanpakutō.
He acted passively his whole life, letting others decide his fate. What did he receive in exchange? A life of mental anguish and a lead bullet through his head.
This time, he had knowledge of the future, the power to switch races, and a ridiculously useful System. He possessed all the necessary tools to become strong and live on his own terms. How pathetic would it be if he was a doll dancing on Aizen's palm?
"It won't happen."
Just the thought of being manipulated like a pawn made him feel all sorts of emotion. After all, he had no control over his previous life. No freedom to decide his future or even the freedom to leave home outside of curfew hours.
He despised such a life with passion.
His eyes behind the mask suddenly widened as an epiphany dawned on him.
He vied for control all his life. A rebel who always wished to resist his grandfather's control. That control slowly slipped away, and he had to live under oppression—that was his life's biggest regret.
[Aspect of Death realized.]
[Innate Ability: Aspect of Death 'Oppression' unlocked.]
Laughter erupted from him as if insanity had taken hold of him. The cave reverberated with his maniacal cackles.
"Death by Oppression. Ah, this is perfect. I love it."
Apacci wondered if the brutal nature of Hueco Mundo had shattered his sanity in a day. "O-Oi, don't lose it. You can fight it. Push down your instincts!"
He turned to Apacci with a grin, his terrorizing aura emphasized by his menacingly glowing eyes. "What do you mean? I'm a perfectly sane human being… Yes, I am."
Apacci couldn't help but miss his gentle, considerate voice.
'This ruffian Kazuya sucks.'
***
Kazuya didn't step outside the cave that day. He wasn't looking to achieve Hikkikomori status in Hueco Mundo. To truly grasp the concept of Arrancars, he had to get acquainted with the basics of being a Hollow.
He opted for 'closed door cultivation' to hone his Vasto Lorde strength and unlock the full potential of his new innate ability. The Evolution Database provided the basic knowledge while his own mind filled the gaps.
Firstly, Hollows weren't the mindless soul-eaters the Soul Society portrayed them as. In fact, Bleach clearly showed that Hollows were different in many ways. The more he learned, the more intriguing complexities arose, complicating his intended path.
Many questions swirled in his mind: Why did a Hollow have a mask? Why did they consume others to fill the void in their souls? What was the nature of the void that expanded with their craving for souls? Why did most Hollows become more human-like after reaching the Adjuchas-Class?
And most importantly, what exactly was this Inner Heart that triggered the creation of a Hollow?
He had numerous theories, but none could be confirmed. Eventually, he abandoned the pursuit of the Inner Heart's true purpose and shifted his focus to Hollow evolutions.
Every evolution after Gillian placed great emphasis on suppressing raw instincts. The raw instincts that turned them into hyenas for souls instead of flesh.
Why was it the strongest state of Hollows—Arrancars—resembled Shinigami?
He kept looking for answers.
Hours passed away in the same cave.
For Apacci, this was nothing unusual as she, too, had slept for days at a time in the past. Her new schedule was sitting there and staring at his face, then returning to sleep. Did she miss interacting with him? A lot more than she wanted to admit. But she couldn't complain much as this was still miles better than her old life. She didn't have to be concerned about being devoured all the time now when her own companion was a Vasto Lorde. She had never experienced such peace her whole Hollow life.
And staying with someone's warmth felt… quite nice.
Half a day passed by and Apacci was starting to feel an unease, which had nothing to do with Kazuya's state.
She was sitting next to him and watching him cycle through multiple expressions. Unrelated to him, she also felt a multitude of emotions in her chest, more emotions than she had felt her whole life. Perhaps it was because she had been doing this same ritual for hours now—whatever it was… she had this intense urge to lick his face and bite his neck, playfully, of course. It was such a stupid thing to do, but she was finding it harder and harder to stop herself.
Soon, things got to a point she had to leave to distract herself.
This was torture for poor Apacci, who couldn't, for the love of god, understand her urges.
When she returned from a walk outside, she sat next to him and pressed her face in his arm.
'Come back… I miss you.'
She looked up at him and saw him looking at her. The look in his eyes was different—he felt like a different person.
Kazuya took a deep breath and let go. After his 'closed door cultivation', he felt like a hermit who had achieved enlightenment. He finally understood the concept that had eluded him until now.
'Menos don't eat others to become strong and evolve.'
The primary drive for devouring other souls in Menos—it was to strengthen their consciousness. How did eating souls do that? It was quite simple. Menos assimilated some aspects from those they devoured, which in turn progressed them toward losing their 'Hollowness', toward becoming 'whole' again.
This was how Menos suppressed their raw instincts and why Adjuchas and above evolutions weren't monsters but rather human-like in consciousness.
Failure to achieve this 'wholeness' in time would result in regression to Gillian-Class.
The theory made too much sense to be false or delusional.
'Then Arrancars...'
His lips curved into a smirk as he realized the true intent of tearing the mask for Arrancarization. Aizen was right about 'separating boundaries between a Hollow and Shinigami' to create an Arrancar. But there was more to the process; otherwise, there wouldn't be natural Arrancars like Ulquiorra Cifer and Coyote Starrk.
'Let's test my theory and my new ability.'
He noticed Apacci giving him an odd look, so he reached out and patted her face. "What's the matter?"
She quietly shook her head. "I was wondering… when will this silly guy wake up? Is your sleep over?"
"Yup, we're done."
"Hmm… where are we going now?"
"To cause some chaos, my little friend. Let us toy with the destiny of some hapless souls."
"..."
Apacci wondered if he had lost his mind. Over half a day spent sitting in one spot may have broken him. Honestly, she wouldn't feel burdened if he did go bonkers. At least then she wouldn't feel ashamed to give into her impulses… and finally lick his face.