あらすじ
An unsettling job came to Hina, an extremely shy girl. It was to become the contractual fiancé of Amane, the head of the Gionji family, a prestigious noble house in the Imperial Capital!? While feeling a sense of unease in the mysterious atmosphere of the Gionji mansion, Hina spent her days as his fiancé, only to discover that Amane is an Oni hiding in human society――. Meanwhile, in the Imperial Capital, incidents of young noble ladies disappearing are occurring repeatedly……?