A son starts living alone in a one-room apartment in the city. His parents take a train from the countryside to visit him in Tokyo. Seeing the messy six-mat room, his kind stepmother Rika says with a smile, 'Let's tidy up a bit,' and efficiently cleans the room. That night, the father suddenly returned to his hometown, so the stepmother stayed at her son's apartment. They laid out futons side by side in a six-mat room, and as the stepmother slept soundly, the son's dick couldn't take it anymore and got hard…!
