The war between Idéal, the country of demon race, and Étoile Kingdom, the country of the human races, had been going on for a long time until a peace overture was offered by the demon lord. Following this, the demonic princess, Lieselotte, was married to the Hero, Schmerz and she'll live in the human world as a hostage of sorts. However, this is just Lieselotte's first step toward her ambition, and her future will be full of hardship that she must overcome...
