Incest Cuckold Story A husband unexpectedly gets an erection after watching his wife and son having sex

Her husband, Kouichi, is excited about his nightly activities in order to please his young remarried partner. However, because of my age, I don't get erections as much as I would like. Koi, who was fed up with her husband, began to have a physical relationship with her son-in-law, Hajime, at home. One day, Kouichi happened to witness the scene of the two having an affair, and unexpectedly noticed that Bad Son had become hard in front of the scene. Excited to see his second wife and son's unforgivable acts, Koichi lies that he will be away from home on a business trip and masturbates while watching them...