On a hot summer day, Naoto Kamino finally confesses his feelings to his crush, Manabe Rika, only for their moment to be interrupted by a devil named Asmodeus who tries to kidnap her. Rika holds a secret power that allows her to transform into the magical warrior Sei Tenshi Djibril, gaining powers through intimate acts to fight the forces of hell. Joined by the angel Luvriel, they battle demons in a supernatural conflict where love and desire fuel their strength.