Ryoko, a high school student, is the heir to a yakuza family, but keeps it a secret at school. One day, Shijo, a delinquent who got into a fight with the yakuza, goes missing, and Shinichiro, who tried to help Shijo, is kidnapped as well...

Yuki and her boyfriend Makoto seem like an ordinary student couple, but in fact, they both have a shocking secret: their families are gangsters and they have been dating without revealing their true identities to each other. When Yuki's father suddenly dies, Yuki has to become the third generation leader. Then an incident triggers a conflict between the two unions...