Mio is a beautiful wife whose married life in the apartment complex has settled down, and she has begun thinking about having children. However, her husband is passive not only about making babies but even about their nightly intimacy, leaving her with an unsatisfied sexual appetite that she occasionally relieves by masturbating. One afternoon, while stroking her sensitive spot alone, she looks up and locks eyes through the window with Takeshita, a middle-aged neighbor who has come to introduce himself after moving in. The two, who were never meant to cross paths, use this witnessing of her masturbation as a catalyst to enter into a relationship of intense, sweaty affairs...
