Yakumo Rio and Yakumo Miyu, it lived by family matters in a special little while environment. Though two people who had lost parents when it is young were received by the grandfather, that grandfather “Yakumo class” it was a leader of the class. The grandfather thinks that it wants you to live in the world without relating by himself in the granddaughter, they are not made to be related to work and the custom etc of the class as much as possible, it has raised it as a very usual girl. However the situation changes completely because the grandfather succumbed by the sickness. In an intensifying territorial dispute, Yakumo class lacking boss will not stand, The Fuzen no tomoshibi becomes a class. Having held out the hand to that sort of situation, Yakumo Class was expelled once, it was Takashi Inami who was the leader of the Inami class. As a condition of helping, the condition that he proposed for a certain period, the thing that presented Miyu or Rio as my woman. To protect Rio an important place and the person, it make up my mind to live as a woman of gang leader Inami.