Warm body and soul, incestuous kotatsu

His mother, Shizuka, remarried Genji, and Susumu had a stepfather around his age. Genji did not think well of Susumu's presence, and the family was strained. Even during meals, Susumu endures a lot of sarcastic comments from Genji, and Shizuka's presence is the only thing that saves him. Susumu and Shizuka had a deeper relationship than before... However, with Genji's arrival, Susumu can no longer indulge his mother confidently, and his desire has increased, and while pretending to be calm, he begins to seek out his mother's body in the warmth of the kotatsu surrounded by the three of them...