Leaving Seireitei

Seeing Yuna defeating everyone that was trying to stop him, Aizen nodded in approval while secretly being surprised at just how strong she actually was. Although he had seen her fight Rangiku and Kira, she barely showed off her strength during that fight. But now that she revealed that she could easily handle Ichigo and Renji, Aizen had to admit that he had underestimated her quite a bit. Obviously, he didn't think that that would have any negative consequences for his plans. After all, Yuna has already seen his Shikai release, making it impossible for her to fight him.

He briefly wondered how Yuna knew that he was acter Rukia, but considering all the things that had happened so far, it was rather obvious that his plans revolved around Rukia's execution taking place., making her his most likely goal.

As these thoughts passed through his mind, he noticed Ichigo struggling to get up, causing him to smile lightly.

"Poor thing. Not only can you barely stand due to your wounds, but the one who struck you down was even someone you trusted. How pitiful.

Anyway, you made it further than I expected, but that doesn't really matter anymore. After all, your part in this is over."

"M-My part?"

Naturally, Ichigo was shocked that Aizen spoke of him being here as something Aizen had planned for. However, before he could ask any further questions, Aizen started his explanation.

"Yes, your part. You invaded Seireitei, causing chaos and destruction while bringing people on the verge of mental collapse and even defeating Captains. All in all, it was very exciting. In fact, it was so exciting that the death of a Captain barely caused any waves, making my job incredibly easy."

"W-What?"

Seeing nothing but confusion in Ichigo's eyes, Aizen sighed deeply before he continued talking.

"What are you so surprised about? Maybe because I talked like I knew you were coming here? Isn't that obvious? It only makes sense for Urahara Kisuke to send you here to receive his precious treasure."

"T-Treasure? W-What treasure? Rukia? Wait, h-how do you know about Kisuke?"

"Mhh? He hasn't even told you this much. Well, since we have reached this point, I might as well explain it to you.

Shinigami have four basic combat methods: Zanjutsu (Weapon arts), Hakuda (Martial arts), Hohou (Movement arts), and Kido (Magic arts). While attempting to master these four arts, every Shinigami reaches the ceiling of their potential at one point, causing progress to grind to a halt.

Now, the question is: Is there a way to break through that ceiling? The answer to that question is something I have been researching for a very long time, and by now, I know the answer: Yes, through hollowfication."

Hearing the term "hollowfication", an image of him donning a hollow mask during his fight against Byakuya briefly flashed through his mind, giving him an unnerving feeling.

However, Aizen was seemingly unaware of Ichigo's state of mind and was just about to continue his explanation when someone else started speaking.

"I see; by combining two opposing live forms with the same source, one can basically stack their potential from both forms, effectively doubling one's potential. However, I doubt the math works that easily as there should be variations depending on an individual's respective potentials depending on their transformation. After all, just because a human has the potential to become a strong Shinigami doesn't mean he would become a strong Hollow as well."

Hearing Yuna suddenly coming up with an explanation, Aizen's thoughts briefly ground to a halt as he looked at Yuna in bewilderment. Obviously, he didn't show any of it, but Yuna still realized that Aizen was surprised by her words.

'Mhh? Did I say something wrong? I don't think that explanation was that surprising, so what is he surprised about?'

While these thoughts passed through Yuna's mind, Aizen had completely different thoughts.

'Wait a moment. Same source? Right, whether it is Shinigami or Hollow, both were once human. I never put much thought into humans, but this is a rather interesting perspective of the dynamic between Shinigami and Hollow. That might be worth looking into.'

Despite the actual explanation not exactly fitting Yuna's words, Aizen still nodded his head as the core of her words was correct: By breaking the barrier between Shinigami and Hollow, someone can increase their potential and reach greater heights.

"Indeed. I'm surprised you figured that out so quickly."

"Well, I AM and genius, so that much is only natural."

While Aizen and Yuna were happily chatting with each other, Ichigo could only look at what was happening in front of him with bewilderment. The fact that Yuna had no trouble chatting with Aizen while completely ignoring him made it even clearer for him that she had sided with Aizen.

"Anyway, a lot of research went into this subject, not just from my side, but most people were hindered by ignorance and worthless ethics, preventing them from truly reaching their full potential."

While Yuna nodded in approval due to Aizen's opinion about ethics, Ichigo could only continue listening with a combination of anger and helplessness.

"However, around a hundred years ago, someone finally made a breakthrough and created a substance that could destroy the wall between Shinigami and Hollow instantly. That man was Urahara Kisuke, and he called that substance: Hogyoku.

Unfortunately, he thought this substance was too dangerous, so he tried destroying it, which he luckily failed at. So, instead of destroying it, he sealed it away in a container that would make it possible to plant it into someone's soul and hide it away for forever."

Ichigo and Rukia's eyes widened as both of them got a pretty good idea of what Aizen was currently implying.

"It seems that you have understood my words. Yes, the soul the Hogyoku is hidden in is Kuchiki Rukia's."

Obviously, the duo was shocked by that revelation and looked at each other in utter bewilderment. Only now did Rukia realize how weird everything was. The fact that she never recovered her Spiritual Power despite spending so much time should have already made it very clear to her that things were fishy, but she had never put too much thought into it, resulting in the current situation.

"Seems like you have finally grasped the situation. Yes, Urahara Kisuke never tried to help you. He gave you a Gigai that would prevent you from regaining any of your Spiritual Power while slowly draining what little you have left, resulting in you turning into a human permanently and hiding the Hogyoku forever. Well, at least until you died and returned to Soul Society."

Rukia couldn't help but be shocked after getting told how Kisuke tried to use her. She never trusted him 100%, but this was too much for her to fathom. So, all she could do was look at Aizen, utterly dumbfounded.

"Oh well, I still managed to find you, and as soon as I did, I killed the Central 46, giving me a convenient place to stay while allowing me to use the Central 46's authority to wield Seireitei's Captains as I wish.

As far as I knew, there is only one method to remove a foreign object from a soul: Burning the soul with the heat of the Sokyoku. However, how can I be satisfied with having only a single path I can walk on? So, I dove into the archives under the headquarters of the Central 46 and looked through all of Urahara Kisuke's research. After all, if he can devise a method to store something inside a soul, he surely has a method to extract it as well.

Lucky for you, Rukia, there was such a method."

As soon as he finished speaking, a small device appeared in Aizen's hand, which he quickly activated, resulting in his hand getting coated in a weird wire-like substance.

Aizen briefly looked at his now coated hand in fascination before stabbing it toward Rukia's stomach, where a huge black hole opened just when Aizen was about to touch it.

Unfortunately, Ichigo was too far away to see what just happened, so the scene in front of him looked like Aizen's hand had just stabbed into Rukia, causing him to start yelling at Aizen.

Aizen ignored Ichigo's yes and pulled a single crystal-like object out of Rukia's body. It looked like it was made of transparent class and had an almost Rasengan-looking black ball floating in its middle.

"So this is the Hogyoku."

While Aizen was looking at the small crystal in his hand in fascination, Ichigo tried to raise his body somehow, but no matter what he did, he couldn't stand up. He only calmed down when he noticed the hole in Rukia's body closing, leaving no wound behind.

"Impressive; despite something getting extracted from a soul, there is no wound left behind. Oh well, you are unfortunately no longer needed, so, Gin, kill her."

Gin, who had been quiet up until now, simply raised his sword as the smile on his face grew even creepier.

"All right. [Shoot to Kill, Shinso]"

The moment he finished speaking, his Zanpakuto extended and shot towards Rukia, tip first. However, just when it was about to reach her, a hand appeared out of nowhere and pushed against the flat side of the place, resulting in it barely missing Rukia. Simultaneously, Byakuya appeared next to Aizen and moved Rukia away from the blade while putting himself in its path.

"Oioi, that is not the deal we had, Aizen."

*Rumble*

The air shock as Yuna's Spiritual Pressure briefly spiked, causing everyone present except for Aizen to briefly choke. Obviously, she was the one to direct Gin's blade away from Rukia, allowing both Rukia and her brother to dodge the attack.

Feeling the intense Spiritual Pressure radiating briefly out of Yuna, Aizen couldn't help but raise his high brows. He had already known that the current Yuna was stronger than Ichigo had been before his Hollow started interfering, but he didn't expect it to be to such a high degree.

'She keeps getting more and more fascinating. It has reached a degree where she even might be able to interfere with my plans. I should kill her right here, right now, but I won't. This is exactly what I need. Just like Gin, who I know will betray me at some point in time, she will be another factor that will put pressure on me, pushing me towards breaking all limits and allowing me to reach my goals.

It's truly a pity that she was born as a nobody. The final level of my evolution won't be something a normal person can reach, no matter how talented. Only Kurosaki Ichigo, who has the blood of a pure-blooded Quincy and an especially strong Shinigami, could possibly reach the level of power I desire.

There is no way someone without certain base qualities could ever become a god. Never.

Despite that, I'll continue keeping my eyes on her. Maybe, just maybe, she will turn out to be someone capable of entertaining me as well. I'm looking forwards to how far she can push herself.'

"Oh, I briefly forgot about that promise. Oh well, guess we might as well leave then."

Although Yuna was still not entirely satisfied with Aizen's answer, she could also tell that he was aware of Byakuya's presence approaching them.

'Why is he so hell-bent on playing the villain role? Is he... provoking Ichigo? I see; he still has some weird grooming plans for Ichigo, so he continues provoking him, so he pushes himself more, huh?'

Suddenly, a presence appeared behind Yuna, holding a knife to her neck while another hand restrained her sword arm, while two soft pieces of flash pressed against her back.

"Yuna, what the hell are you doing!? Why are you siding with Aizen!?"

Realizing who had just appeared behind her and that said person was pressing a knife to her neck, Yuna couldn't help but get flustered.

"W-Wait a moment, Yoruichi..."

Although Yoruichi couldn't help but squint her eyes at Yuna getting flustered for once, she still held her weapon, steady, ready to react whenever necessary. However, after Yuna continued speaking, she almost slid her neck by accident.

"... didn't you say you aren't into doing it in public? You are kind of sending me mixed signals here."

"What the hell are you even talking about!?"

"Yoruichi-sama, don't bother with her and just cut off her head., She deserves it."

While Yoruichi was confused by Yuna's words, clearly not understanding how Yuna interpreted the current situation, Soi Fon, who had Aizen in a similar position to how Yoruichi had Yuna, decided to throw in a comment. However, before she could react to Soi Fon's words, Yuna continued speaking.

"Yoruichi-'sama'? Nice, I'm slowly understanding what kind of play this is."

"THIS ISN'T ANY KIND OF PLAY!!!"

"I agree; it's much more realistic when we pretend it isn't."

"THIS IS NOT A PLAY; I'M ARRESTING YOU!!!"

"Ah shit, I'm sorry about that. Obviously, you want to be the dominant one this time, so give me a second."

Before Yoruichi could understand what was going on, Yuna's demeanor changed as her shoulders sagged and an afraid expression appeared on her face.

"Y-Yoruichi-sama, p-please don't hurt me. I-I-I will do whatever you want."

Blood almost started gushing out of Yoruichi's nose when Yuna suddenly started speaking all meek. It certainly didn't help that a massive blush appeared on Yuna's face when she said that she would do whatever Yoruichi wanted. Luckily, or maybe unluckily, Yoruichi wasn't so weak-minded to get trapped by Yuna's acting, resulting in her calming down after taking a few deep breaths.

"I'm serious here, Yuna. What is going on?"

Seeing that Yoruichi seemed to be genuinely worried about her, Yuna decided to stop playing around and simply shrugged her shoulders.

"Well, I have my own goals and ideas, so there is no need to worry. Just like you and Kisuke played your own game without telling us anything, I have my own plans as well. Frankly, there is no need to get worried or angry at me as I have everything planned out. If you want more details, just ask Naruto. He should be able to tell you a little bit more about me and how I act."

Although Yoruichi couldn't help but feel a little guilty when Yuna mentioned Kisuke's hidden plot, in the end, she should only accept Yuna's words and ask for details when the situation was more appropriate.

After all, Aizen's little group was currently surrounded by every available Captain and Lieutenant within Seireitei, creating quite a huge group.

"This is over, Aizen. You are surrounded on all fronts."

Hearing Soi Fon's words, Aizen couldn't help but chuckle in amusement as he looked upward, where cracks appeared in the sky. Moments later, dozen of Menos Grande appeared as the cracks turned into a huge opening.

However, that wasn't all, as the Menos Grande moved to the side, revealing a colossal creature with a single massive eye. Obviously, that scene flustered every Shinigami present, but before they could do anything else, four beams of light descended from the sky and covered Yuna, Aizen, Gin, and Tosen in a pillar of light while forcing those who held a weapon to their neck to back down.

Moments later, all four of them started floating upwards towards the freshly opened hole in the sky.

"Oh well, see you later, Yoruichi~"

Seeing Yuna getting separated from her and floating away, Yoruichi couldn't help but grit her teeth while not really understanding how she was supposed to feel right now.

Obviously, she had only known Yuna for a short time, but this whole situation still didn't feel good. The matter of joining Yuna's harem aside, Yoruichi, at the very least, considered Yuna to be her friend, so getting left behind like this wasn't nice at all.

Additionally, she thought that she had a pretty good grasp on Yuna's personality by now, and leaving like that didn't fit her at all. On the other side, she had only known her for a short while, so there might be things she hadn't understood about Yuna yet.

All she could tell right now was that the current situation SHOULD feel like Yuna betrayed her, but it DIDN'T, confusing her only further.

'Guess I'll just ask her brother as she told me to. What was his name again? Naruto, right?'

While Yoruichi was contemplating the current situation, Aizen looked down on the masses, and moments later, Ukitake started speaking to him.

"Why have you sided yourself with the Menos?"

"To reach greater heights."

"Heights? Haven't you fallen?"

Hearing Ukitake's question, Aizen could help himself but show displeasure on his face.

"Fallen? Don't kid yourself, Ukitake. No one ever stood above the heavens before. Not you or I... or the gods. However, the unbearable vacancy of the throne of the heavens ends today."

As Aizen was speaking, he slowly took off his glasses, revealing a pair of eyes filled with nothing but ambition, and following that, he combed back his hair, totally changing his image from a soft-spoked person to someone who deemed himself fit to rule the world.

"From now on, I will stand at the top."

As soon as Aizen finished speaking, he vanished inside the previously opened crack in the sky, leaving Seireitei behind.

"That sure was a grand exit, huh? I'm sure nee-san got a thrill out of that~"

Hearing someone speaking in a leisurely manner, everyone's eyes snapped toward the source of the voice and saw a young man with long blond spiky leisurely watching everything unfold with a smile on his face.

It took a few seconds for everyone to comprehend the words that were just spoken, but when everyone realized that the blonde young man called Yuna "nee-san" all of them took action simultaneously and drew their blades, pointing them at the young man, causing him to chuckle with a wry smile on his face.

"She sure likes making trouble for her little brother, huh? Oh well, let's see where this goes~