After his convenience-store shift, a torrential downpour leaves him unable to get home. Yuri Adachi, his cheerful, petite adult junior coworker who feels like a younger sister, invites him to stay at her place. Once they arrive soaked, she changes behind him and reveals huge breasts he never could have imagined beneath her clothes. Then she presses them against his arm and openly tempts him, drawing him into repeated cheating sex.