Raised on tales from his mother about Lord Tenran, the stunning and dignified demon king of the east, Asagi's ancestry as a dragon promises that he will someday serve Lord Tenran like his mother did. However, when that day inevitably arrives, he is greeted with a harsh truth: Lord Tenran is not only boastful and crude, but he also has a penchant for playing the submissive role and enjoys toying with Asagi's affections.