Kinshin Bokan ~Kyou mo Mata, Okaa-san ga Boku o Motomete Kuru~

The protagonist, Miyasaka Takayuki, is lying in bed trying to fall asleep when his mother, Miyasaka Kaori, enters the room and asks if he's asleep. Takayuki has flashbacks to a time when his family was happy before his father died and his mother remarried. Kaori has developed an unhealthy obsession with her son and they engage in a twisted relationship. Takayuki knows that this cannot continue and hopes that his mother will come to the same realization.