"How long has it been? 3,000 or 4,000 years? Aizen has long lost interest in counting. His dream of leading the Soul Society has faded. Does the Soul Society still exist? After so many years, everyone he knew has long died. Of course, Aizen didn't care about anyone, but what is the point of leading people who don't even know who you are? What is the point of wanting to lead a place which you don't even know if it exists anymore?

Aizen has long been comfortable with the idea that he has been forgotten. After all, the only thing he could do here is train in his inner world or think. His strength has reached a point where he could beat Yhwach alone, but no matter how strong he was, he would not be able to free himself from the seals. After a point, Aizen gave up on this life. The only thing that he could freely access with all these seals was his soul. After many years and many tries, he found a way to create a soul imprint with all his memories using the Hogyoku. His plan was simple: reincarnate together with his memories.

Finally, the day arrived. Aizen was excited. He already knew the process of reincarnation. After all, as a Shinigami, he has guided many souls to the afterlife. With the help of Kyoka Suigetsu, Aizen sacrificed his body to the Hogyoku to free his soul. It was a difficult process with many steps that Aizen had carefully planned.

However, something unexpected happened. As soon as his soul left his body, Aizen watched his old body smiling. It was a truly alien smile not fitting for a living being.

Aizen had long overcome fear. He believed himself incapable of feeling fear anymore, but now the long-lost feeling was starting to come to the surface again. 'The only thing keeping the Hogyoku in check was my soul and mind. It managed to affect my thinking and make me not think of this scenario. Fascinating!'

The Hogyoku took control of the body, but it wasn't able to free itself from the seals immediately. However, it couldn't let Aizen escape. Its instincts were screaming. If its previous host escapes, he would find a way to enslave it again. This man was terrifying.

In panic, the Hogyoku did the only thing it could at this moment. It used its effect on this world to open a portal to the outer cosmos. If it could not kill him right now, it would send him to a place where it would be impossible to come back.

Aizen was ecstatic from what he was seeing. He had a mixture of feelings: fear, excitement, fascination. The Hogyoku created a pull to his soul and connected it to the outer cosmos. He was unable to move. There was no point in resisting because it was out of his range of powers in his current state.

However, he didn't even want to resist. Outer cosmos, a new beginning with so many possibilities! His curiosity got the better of him. Finally, his soul went into the portal, and he lost consciousness.

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In another world far away, Uchiha Itachi had just completed his mission. He eliminated his clan and managed to stop the coup d'état. It was time to face his little brother. He wanted to cry so much, he wanted to scream, he wanted to end his life but he couldn't. He needs to do this.

He proceeded to use his Tsukuyomi for the first time. For 48 hours, he showed Sasuke the death of his clan. He knew how much Sasuke loved him, but this love would lead his brother to his death. If Sasuke started asking questions and found out the truth, he would proceed to destroy the village, and Itachi already knew the outcome. His brother would die. The other option was to take Sasuke away. However, the life of a missing nin, a ninja who will join the Akatsuki, is not suitable for children.

After much thought, Itachi decided to make Sasuke hate him. This option had many advantages. His brother would become strong to kill him. His brother would awaken his Mangekyo after his death. His brother would take revenge for his clan, and finally, Itachi would find peace in death.

However, Itachi made a crucial mistake. This was the first use of his Tsukuyomi, and Itachi underestimated its power. He wanted to make Sasuke hate him but not traumatize him to this degree. He wanted to make Sasuke lose consciousness but instead left him in a coma.

He wanted to help him but he ran out of time. Madara could not wait any longer. What Itachi hadn't realized was that his brother's soul was already destroyed beyond repair. For the body to be intact and the soul to be missing, it was a truly rare phenomenon in this world. The chakra reacted and started searching for a way to restore the balance. If it was unable to restore the balance, the body would die too.

However, for the first time in the history of this world, a solution was found. A soul without a body with a sleeping consciousness. The soul of Aizen Sosuke. The soul was attracted to the new body like a magnet. The balance was restored.

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After 2 days in a coma, Sasuke started to regain his senses. An influx of memories immediately filled his brain. It was both the memories of Uchiha Sasuke and the memories of Aizen Sosuke. However, there was no confusion. He knew who he was.

He was Aizen, and there was no way that the broken memories of a small child would manage to shake him. After all, he had lived for thousands of years and had reached levels of power unheard of in this world.

'A new world with a power called Chakra. A world filled with ninjas. I am part of the village of Konoha and a member of one of the strongest clans, the Uchihas. I have one of the strongest kekkei genkai, Sharingan. I haven't felt so excited since I created the Hogyoku.' Aizen thought. 

Aizen didn't open his eyes. He was in an unfamiliar environment. His new identity is Sasuke, and he knew what happened with Itachi. Aizen knew that if he let himself open his eyes, he has to answer questions.

'I need to analyze the memories of Sasuke carefully. I need to make careful plans and proceed with caution.

The first problem is that I have to keep my new identity a secret. According to the previous memories, there is a clan in the village, the Yamanakas, who can read my mind and are used as psychiatrists. After an incident like that, I am sure that they will demand to examine me to check if I am a liability to the village.

The solution is pretty simple. After a thousand years with my mind and my inner world as companions, I can easily create a memory palace and hide the memories of my new identity. I must also create an image of a scared traumatized child who is scared of his brother and loves his village. I want to promote the idea that my plan is to restore the Uchiha clan and make it the greatest clan in Konoha. I may even want to promote the idea that I want to be Hokage to stop similar incidents in the future.

At this stage, I don't have the power to create fake memories. I lost my zanpakuto, and I cannot feel spiritual power in this world. Chakra has a similar sense, and it feels like it contains spiritual power but only as a part of the whole. I need to study everything I can because Sasuke's knowledge is extremely limited.

I need to spend a lot of time reorganizing Sasuke's memories to promote the fake image. I need to put them at the top of my memory palace. If the Yamanaka decide to see further, I need to create several defensive layers with memories of my trauma with Itachi. Under these layers, I need to create even more layers with the memories of the love that Sasuke received. I don't think that they will look so deep, but better be paranoid than risk it.

Another field that I need to study is the laws of the village. I know that there is a council that family heads take part in and help the Hokage make decisions. I need to find out the criteria to take part in this council.

Of course, I need to find out more about my brother. There is no way that a ninja of his age managed to kill a whole clan without help, no matter how strong he is. According to my memories, that situation in the clan was a little tense, and the clan was too crowded the last days. Sasuke didn't focus on this, so I don't have enough information. However, there is a possibility that the village is involved. Maybe the clan was too crowded because they recalled all the ninja to annihilate them all together.'

Aizen took his time. He analyzed every memory and made several plans for the next months. After a week, he finally opened his eyes.