Next-door housewives Ayako and Hitomi have long shared a close friendship. One afternoon, while casually chatting over tea, Ayako mentioned her knee pain, prompting Hitomi to naturally begin giving her a massage. As Hitomi gently kneaded Ayako's body, she became overwhelmed by desire upon seeing Ayako's reactions of pain and pleasure. In that moment, Hitomi kissed Ayako. Surprised, Ayako hesitated but gazed back with longing eyes—just as Ayako's husband unexpectedly returned home. The two reluctantly parted, promising to meet again. From that day on, Ayako remained restless, unable to forget the memory of that kiss.