Under the scorching heat of midsummer, Rin and her childhood friend attend a festival. A sudden downpour forces them to take refuge in a car. In the closed room, her childhood friend's genitals swell as her wet, see-through bra and her cleavage drips with rain. The two, who had never seen each other as the opposite sex, lose all sense of reason and, forgetting about their respective lovers, make love in the car. An NTR story that begins with a sudden rain shower.