Chisato suddenly comes over because she is worried about her daughter who has started living with her boyfriend. However, even though Chisato is with her, she doesn't even try to hide her lovey-dovey relationship, and ends up getting excited by the two of them. At night, as she sleeps in the river, her body begins to tingle as she hears the faint sounds of panting from next to her. Even though she knows she shouldn't, her voltage increases every time she hears the sound of her clothes rustling. Chisato finally reaches the limit of her patience, and while they are asleep, she straddles her daughter's boyfriend and has sex with her while she sleeps with him...
