In the human world, there live demonic invaders named Shinma who prey upon the fragile souls of humans. The only hope for the humans is one of demonkind: Miyu, who is fated to destroy the Shinma and send them back to whence they came. Although half-human herself, as well as living amongst them as a typical high school student, she bears no compassion for those she saves, as well as condemns. Along with Larva, her subservient, Miyu sets out to destroy evil, one Shinma at a time.