[Edit]Rin Okumura was a troublesome child. With his extreme short temper and violent ways, many people (as well as himself) question his humanity, only to be told by his adoptive father Shiro Fujimoto, priest and exorcist, that he is indeed human. At age 15, Rin discovers that he is not only a demon, but the son of Satan himself. After Satan possesses and kills his father, Rin is determined to become and exorcist and defeat Satan.