Akari has been married to her very kind husband, Takuro, for five years. Although she is happy, she feels that their sex life is too gentle and a little lacking. One day, when she complains about her husband over the phone to a female friend, she is encouraged to have an affair once in a while. "It's okay, as long as you don't lose interest in him," she says. However, finding a cheating partner isn't easy, so she asks her former colleague, the playboy Kitagawa, for sex. This is a fresh and new experience that excites her. Having gotten a taste of infidelity, she then invites her former boss, whom she admires, to have sex with her. Akari, consumed by gentlemanly sex, continues her affair, and although she feels guilty about her husband, her feelings gradually begin to grow. One day, when her husband surprised her with kindness on their wedding anniversary, she realized that she was happier with him after all, and her feelings returned. She thought it would be a happy ending, but she realized that happiness and sex are different, and she continued to have abnormal sex with the playboy Kitagawa.