One of the cliffhangers from the Bleach Thousand Year Blood War arc is what happens to Sosuke Aizen after he assists Kurosaki Ichigo, Abarai Renji, and Uryu Ishida in defending the Soul Society. Known as the ‘Chair Aizen’ version, the former Captain locks horns with Ywach The Almighty at the end of TYBW.
Season 1 of Bleach Thousand Year Blood War, titled The Blood Warfare, featured Ywach telling Shikeguni Genryusai Yamamoto that he went to the deepest underground prison in the Soul Society to recruit Aizen. However, the latter refused. He always wanted to be the one in power rather than being someone’s subordinate.
Bleach Manga readers know how Aizen conjured a Hado #99: Gonryutenmetsu on Ywach during the final battle alongside Ichigo. It failed due to ‘The Almighty’ power after which the villain rended Sosuke’s left arm with his immense Reiatsu. Disappearing from the battle, what happens to Sosuke Aizen at the end of Bleach TYBW?
Sosuke Aizen was imprisoned after Bleach Thousand Year Blood War
After Ywach is defeated, the story of Bleach fast-forwards to ten years later. The Soul Society, which lay shattered due to the attacks by the Sternritters, was still in development. We also come to know what happens to Sosuke Aizen at the end of Bleach TYBW, thanks to a brief yet iconic scene underneath the First Squad Barracks, where the Central Underground Prison was situated.
Aizen is seen back in the Muken after the end of Bleach TYBW. The whole scenario is vividly described in the canonical events in Bleach: Can’t Fear Your Own World. Given that he was back in the prison, he must have been knocked out by Ywach’s attack following which the Central 46 captured him. The fact that he was coughing up blood after being hit further justifies this assumption.
Sosuke Aizen has a long conversation with Captain-Commander Kyoraku Shunsui. The latter initiates the convo by asking if Aizen “wanted to breathe the air of Soul Society once more.” However, he needed to sit on the chair on which he was strapped prior to the attack by the Sternritters.
Seated in his chair with seals all over his body restricting his movement and spiritual pressure, Sosuke Aizen is seen amidst the crumbling remains of a foundation in the Soul Society. This means that he agreed to be bonded and went back to the Muken. The former Captain also has a conversation with Shuhei Hisagi about Kaname Tosen.
Kubo wanted to recreate the Hell and Heaven scene in Bleach, where the one buried deep underground, i.e., Aizen, had a deep loathing for the one reigning supreme and having absolute control over the world, i.e., the Soul King. Both are God-like creatures but it is only the Hogyoku-fused Aizen that will continue to gain power even if he is strapped to a chair.
Will Sosuke Aizen return to claim Soul Society? Unfortunately, Kubo illustrating Aizen as a hero means that Ywach Bach was the ultimate villain of the series and there will be no further additions to Bleach.