A son started living alone in a one-room apartment in the city. To check on him, his parents traveled by train from the countryside to Tokyo. His gentle stepmother Rika, seeing the messy six-tatami room, smiled and said, "Let's tidy up a bit," efficiently cleaning the room. That night, the father had to return home suddenly, so the stepmother ended up staying over at the son's apartment. As they laid out futons side by side in the six-tatami room, the son's dick couldn't bear the sight of his stepmother's curves as she slept soundly, and he got an erection.