شیویوکیورو

Zodiac: Aquarius

Tsukishima is the former leader of Xcution, an organization created by himself by gathering people with the same goal as him - erasing their own power. He also had found a way to achieve this by passing fullbringers' powers into a shinigami representative. However, at some point of time, due to unknown reasons, he had a change of heart. He betrayed his own comrades, killed this shinigami and everyone who already had passed their powers into him.

During Lost Agent arc he's trying to prevent Kurosaki Ichigo from coming closer to Xcution, with its new leader Ginjou Kuugo, by attacking his friends.

[Spoiler: Later, it is revealed that he and Ginjou have been working together from the start. Ginjo appears to be his saviour, though it is unknown how. He is later seen supporting Ginjo throughout the remainder of the series.]