Her boyfriend who visits her home with a friend. It's winter. There's a kotatsu in the living room. For various reasons, the three of them end up drinking. Eventually, the boyfriend passes out drunk, not sure if he collapsed or was knocked out. Driven by the momentum of the alcohol and the eros in the kotatsu, the boyfriend's friend's imagination swells and he becomes lustful. In the tense atmosphere where he shouldn't touch the woman with her boyfriend sleeping next to her, he plays a prank.
