After her father-in-law passed away, Hitomi took over her family's public bathhouse. The couple's busy schedules mean they have little time to spend together, and Hitomi feels lonely. One day, a regular customer, Manabu, comes in as a part-timer just before closing time. As Hitomi works there, drenched in sweat, she begins to secretly become interested in him, and a certain incident leads to a relationship. The pleasure of his penis touching her for the first time in a long time awakens the desires that lie dormant deep within the married woman, and she climaxes again and again in the large bath, where moans echo throughout the air.