Living in a shared house in Tokyo, Susumu eagerly anticipated next week's "long holiday break." The reason? He planned to invite his mother, Reiko, to his place the moment his roommate would be away. On the day itself, Reiko arrived at the shared house where Susumu lived. Without a word, the front door opened and their lips met. From that moment on, a 24-hour incestuous affair began, lasting until Reiko's departure. A forbidden relationship unfolds, blending warmth and passion, as the two indulge in relentless, intense pleasure.