Rihito Hiyakawa has a tendency to chase after money, and he isn’t too picky about the means or morals of doing so. His partner, Kosuke Mikado, acts as the voice of conscience, the self-designated worrier in the relationship who wants to take care of Hiyakawa and their friends. Each of the men has his own reasons for making the decision to help fellow exorcist Erika Hiura free herself from the sinister cult led by "the Professor," a mysterious figure tied to a string of horrific curses.