Five years after marrying the very kind Takuro. Akari was happy, but she felt a little unsatisfied with the couple's sex because it was too gentle. One day, when she told her female friend on the phone about her dissatisfaction with her husband, she was encouraged with "Isn't it okay to have an affair sometimes? It's okay as long as your feelings don't change." But there was no way to easily find an affair partner, so she asked her former colleague, a playboy named Kitakawa, to have sex with her, and Akari was consumed by the fresh and new sex. She came to know the taste of adultery. This time, she invites her former admired boss and ends up having sex. Akari, who is burning with passion for gentlemanly sex, continues to have an affair, and although she feels guilty towards her husband, her feelings gradually shift as well. One day, she realizes that being with this person is still happier, touched by her husband's surprise on their wedding anniversary, and her feelings return, but she continues to have abnormal sex with the playboy Kitakawa, thinking that happiness and sex are different.