“Haru Shibasaki will infiltrate a men-only sauna. If nobody notices, she wins a ¥100,000 travel voucher and time off.” Swept along by the producer, she reluctantly accepts, changes in the locker room, washes beside customers, and enters the sauna. Haru may look boyish, but her body is too sexy to conceal, and she is quickly exposed and penetrated in the bath, sauna, and changing room.