Eibon

Eibon (エイボン, Eibon) is an enigmatic sorcerer and former acquaintance, if not friend of Shinigami, who is revered for the creation of numerous Demon Tools , including Brew. As one of the eight Great Old Ones (旧支配者, Gurēto Ōrudo Wan), his "wisdom" (知恵, chie) and very existence drives men to madness.