Once a month, a woman travels by night bus to visit her husband who lives in Tokyo. On the way there, she becomes friendly with a man who is kind to her, and they quickly become close. Although they both have families, the two are attracted to each other and engage in a forbidden creampie affair on the night bus. When they arrive in Tokyo, they go on a late-night adult date around deserted tourist spots. When they go to a nearby hotel, they have a one-night stand where they both have creampie sex until the morning. Suppressing their desire to take their relationship one step further, the two leave for their respective families.