Misa Kuroi, cute high school girl and good witch, never dreamed that when she transferred to a new school, she would become embroiled in a battle to the death with supernatural forces. When Misa and twelve other girls (one of whom has a lesbian affair with a teacher) stay after school to prepare for an exam, they become trapped by a mysterious supernatural demon. One by one, a robed figure murders the girls in order to create a gateway for a demon to manifest itself. Initially, the other girls blame Misa for the horrific occurrence, and Misa must use all her magical skills to prevent the evil force from completing its mission. However, when her skills are tested as never before, will she survive?