"Is this really a workout...?" On the advice of her childhood friend, Hayato Takahashi, Akari Nishimori decides to join a gym to try to lose some weight. The sports bra feels a little skimpy, but for the sake of her diet, she stoically plows on... Just as she feared, her boobs fall out shortly after beginning her workout. Hayato’s hands go straight for her chest, stroking, groping, gradually working their way south. Insisting that his actions are a training regime known as 'sexercise', Hayato steadily escalates the situation until Akari is a soaking mess. It's not over though... Something hard is twitching against her body...