This is an action & criminal story of a mafia, but the hero is an ordinary housekeeper.

When Takashi Nagumo was a high-school student, he was attacked by street gangs. Luckily, a very impressive & strong guy, Ryuusei Kuragano, saved him. After three years, Takashi becomes a housekeeper and is suddenly involved in the money trouble of his friend. His friend escapes with a large amount of debt and he made Takashi his surety. Then the yakuza take Takashi to their office and demand that he work at the house of the head of the yakuza as a housekeeper until his friend could be found. Takashi meets Ryuusei again there...