For centuries, the town of Eiten survives under the same name for a long time.. a demon queen who sacrificed herself to protect the mankind from extinction and while it isn’t really orthodox for a demon-like her take care of humans alike.. it atleast seems like an attempt to get heaven and hell together. When the demon queen died, Eiten was lucky to pass into modern times.. eventually into a bright city.. where years later, a unordinary girl is reborn..