JUC-545 Nao Kawashima discovers her neighbor's son is not short, leading to an affair

Nao Kawashima, married for several years, grows dissatisfied with sex with her husband. She overhears her neighbor scolding her son Yoshiyuki, calling him "short" after he bought a futon from a door-to-door salesperson. Later, Nao accidentally sees Yoshiyuki masturbating and finds his penis is actually well-endowed, so she goes up to his room.