Worried that she's started gaining weight recently, Aoi goes to a swimming class. However, there were only men other than Aoi. Of course, there is no reason for the men to leave Aoi's ripe body alone, and they repeatedly sexually harass Aoi in various ways. Aoi, who resisted, gradually felt it, and the act gradually escalated, such as wearing erotic swimsuits and being made to swim naked.