After losing her husband, she had been raising their son single-handedly. Her son was about to graduate from college. However, Yuria had a concern. A few years ago, she had once had a physical relationship with her son. One day, they decided to go on a hot spring trip together as a last memory of his student days. The memories of that day resurfaced... the shared hot spring, the private room for two. Even though they knew it was wrong, they gradually lost their reason and exposed their instincts, ultimately engaging in forbidden incest.
