Several years into her marriage, Nao found herself increasingly unsatisfied with sex with her husband. One day, she witnessed Mrs. Yamada, the mother from next door, scolding her son, Yoshiyuki. He had been pressured into buying a futon through a door-to-door sales scam, and his mother flew into a rage, shouting, "You pathetic little son of mine!" Those words stirred something deep within Nao. By chance, she soon after caught Yoshiyuki masturbating. Despite being constantly called "small" by his mother, Yoshiyuki's cock turned out to be impressively large and powerful. Entranced, Nao entered his room and found herself developing unexpected romantic feelings.