Subaru is investigating the death of of a enemy, Kaneyama but before he died, he undertook a project, which was how to teach seven teenage girls how to use black magic to get revenge on people they don't like, but when one of the girls feels remorse, she is told by the other girls to continue with the black magic. Subaru tries to stop them but the girls think that he is their enemy and put a curse on him.

Fifteen girls who went on an expedition to an uninhabited island are left behind because their ship sank. The girls' survival begins.