Being the bastard son of Satan, Rin Okumara has taken all he can face. Now he is alone and unwanted, and on a journey to define himself, before others can.

New cover by _Shirochan Sebastian Michaelis is in a difficult situation. He has been ordered by the demon Lord Satan to serve and protect Rin Okumura. It doesn't help that Rin is training to become an exorcist and kill Satan. And to make matters worse, Rin refuses to accept Sebastian while several demons are out to kill him. How will Sebastian fair facing this difficult task? Well he is one hell of a butler... A black butler and blue exorcist crossover