Worried about his pregnant wife's nerves, the husband welcomes his mother-in-law Yuka into their home. Her support is supposed to ease his wife's anxiety, but the irritation only worsens. Forbidden from smoking, drinking and even masturbating, he reaches his limit. Tormented by frustration, he steals Yuka's underwear while she bathes. The next day, Yuka catches him masturbating with her panties.