The older sister lives alone in the city and leads a luxurious life. She sells her body and becomes a mistress. Then, her younger brother and his friend come to Tokyo from the countryside. The two men are dying to have sex with their sexy older sister. When their father notices this, he has sex with her in front of the two men, enjoying the sight of her hard as a rock. Unable to resist, the younger brother and his friend force themselves on the reluctant older sister.