Yokujô gibo: Musuko o kuu

At first glance, Kozue and Kazuya appear to be a happy couple, but in reality, they are in a sexless marriage—a situation that has persisted ever since Kozue began rejecting Kazuya following the discovery of his infidelity. One night, Kazuya dreams that he is having sex with an unfamiliar, mature woman. Upon waking, he is shocked to find that the very woman from his dream is actually there. It is Yukari, Kozue’s mother...