Baishin

Baishin (白沙, Baishin) was a Shinigami who appeared in the OVA Sealed Sword Frenzy''. He was once a member of the Gotei 13, but went insane killing 63 seated officers before escaping to the human world. Six of the thirteen captains chased him and it took the sacrifice of two of them to seal him away. He eventually broke free and hunted down those with powerful spiritual energy. Baishin found it in Ichigo, sucking out power from him. However, Tōshirō Hitsugaya's interference forced him to flee. At the site where he was once sealed, Baishin once again fought Ichigo, this time with Rukia and Renji at Ichigo's side. However, by sucking out Ichigo's spiritual power, Baishin was able to perform his final release, becoming a living being of swords. He was eventually killed by Ichigo using his own final release, leaving only the zanpakutō Baishin had become one with. His goal was to separate his body, and his zanpakutō, even if he perished.