The demon king Clivehertz has escaped to Earth and has found a new pawn, Kazunori, to help him. However, the goddess Fein has sent her best heroine warriors to bring him to justice and pay for the atrocities he has committed. Although initially hesitant about the prospect of working with a demon king, Kazunori is swayed to Clivehertz's side. After all, Fein's warriors have bonded with the souls of his classmates, and by "saving" them Kazunori can have his own harem of cute girls! During the day, Kazunori lives his normal life, but at night the pair battles the girls, using the demon's powers of corruption to break free their hearts from the grip of Fein's heroine warriors. Will The Goddess's heroines prevail, or will darkness take them?