One day, his father suddenly brings home his new wife, Tsubasa. To his surprise, the woman is very young and is the same age as his son, Shuichi. Just by being there, she exudes a dangerous sexiness. Shuichi dreams of Tsubasa seducing him with her firm buttocks, which makes him feel uneasy. The next day, while preparing dinner, Tsubasa wears a tight skirt that is too tight for his Tsubasa, and he can't stop getting an erection.