Raku Ichijou, a first-year student at Bonyari High School, is the lone heir of a powerful yakuza family. Raku made a pledge to a childhood buddy ten years ago. All he has now is a necklace with a lock that can only be opened with the key that the girl took with her when they left ways. Years later, Raku has matured into an ordinary adolescent, wishing to stay as uninvolved in his yakuza history as possible while spending his school days with his middle school crush Kosaki Onodera. When the American Bee Hive Gang invades his family's territory, Raku's ideal romantic hopes are thrown out the window as he is drawn into a frustrating conflict: