The principal antagonist of the series, he resides in Hueco Mundo together with Ichimaru and Tōsen, commanding an army of Arrancar and Hollows, his ultimate goal being to overthrow Soul Society along with the Soul King and take his place as god of the world. After obtaining the Hōgyoku, he declares his intentions openly. When Ichigo Kurosaki and his friends invade Seireitei to rescue Rukia Kuchiki from execution, he manages to lay hands on the Hōgyoku with an elaborate plan involving Rukia's execution and the attempts to rescue her, manipulating most of the other captains of Soul Society according to his will. Aizen became captain of the 5th Division later on. He framed Urahara for the hollowfication process and forced him to leave Soul Society.ĭuring that time, Aizen met Gin Ichimaru and Kaname Tōsen, and lured them to his side. 100 years ago, Aizen's experiments on Shinigami/Hollow hybrids involved using an unknown method to cause spirits to transform into Hollows, eventually culminating in the creation of the Visoreds.

Shinji kept Aizen under his view during this time because he felt there was something dangerous about him. Aizen spent much of his career in the 5th Division of Gotei 13, eventually becoming its lieutenant under the former captain, Shinji Hirako.

Bleach aizen final form