Kohichi, visiting his classmate Yosuke's house, discovers that Yosuke's mother, Akari, is masturbating while taking a bath. Excited by this, he starts to jerk off on the spot. Noticing this, Akari gently scolds the embarrassed Kohichi and suggests, "Let's enjoy ourselves together." Despite fearing a deterioration in his friendship with Yosuke, Kohichi reluctantly accepts Akari's insistent proposal to "just do it with the tip" as a way for her to relieve her sexual frustration due to her husband's constant business trips…
