Keiko Hattori's husband and son Shinichi had been obsessed with sumo wrestling for several months. This Saturday, they were scheduled to go watch a live match together, and the day had finally arrived. Keiko stayed home alone while her husband and son left for the event. Just minutes later, a young man named Tanaka, whom she had met at her part-time job at the supermarket, came over. He was her secret lover. With a strict time limit before her husband and son returned, an intense day of relentless sex began.