His brother-in-law Atsushi and his wife Naomi are suddenly transferred to stay at the Shiraki house for a while. His wife Yuko welcomes them with open arms at first, but she begins to feel frustrated by her brother's close relationship and the lack of sex... Her frustration gradually grows, and Yuko can no longer contain herself and attacks Atsushi while he is sleeping. Atsushi is surprised by this sudden turn of events, but he is unable to resist her lewd behavior and is swept away by her desires. From that day on, Atsushi becomes the one to release Yuko's endless carnal desires...