Yuka, who has finished raising her children, started working part-time for three years, and during that time, she became involved in an affair with Takahashi, a part-time university student, and was enjoying an illicit relationship. One day, she decided to go to a hot spring on a comfort trip. Of course, Takahashi was among the members on her comfort trip. Yuka, who has a strong sexual desire, secretly invites Takahashi in the middle of the night and enjoys sex, but she is noticed by Kobayashi, a part-time worker who came with her.