Sosuke Aizen is the main antagonist in the Shonen Jump's "Bleach". He was the Squad Captain of Squad 5 before his fake death that happened with the help by Gin Ichimaru. He betrayed the Seretei and became the leader of the Hollows. He is literally the leader of the Espada even though he is a Shinigami(Soul Reaper). His zanpakuto name is Kyoka Suigetsu and its call is "Shatter" as seen when Arrancar #12 thought he killed Espada #4 Ulquiorra, but that was just one of Aizen's tricks to fool the Arrancars to make them think the could kill Ulquiorra and leave Hueco Mundo. After the Arrancar killed the "fake" Ulquiorra, Aizen walked pass Ulquiorra's fake body and said "Shatter Kyoka Suigetsu" and the body exploded into sparks and formed Aizen's zanpakuto in his hand.Sorry I could not change his name from Sasuke to Sosoke which is his correct name 23:24, March 4, 2011 (UTC)Kyori