Change My Heart

Synopsis: Being the son of satan is all good until it isn't. When life just won't stop knocking him over and he decide that he need to relieve stress in some way things just get worse for Rin Okumura.

Alternatively,

Between a crazy headmaster who's a master at head, to a twin brother that did nothing but make him worry Rin would go insane before he could pass the exorcist exam.