During a mixed-gender university club trip, the group stays at a hotel with a private sauna, where Yuri's famously curvy body is revealed in a sweat-soaked swimsuit. Knowing the easygoing adult student role-play beauty would accept a sauna invitation, a man secretly laces the steam with an aphrodisiac. Heat and drugs send her metabolism, judgment, and sensitivity haywire, beginning a long night of making the healthy, big-titted beauty cum until she loses control.