A year ago, Reiko, a beautiful and kind mother who came to remarry. She lives in a new home with her husband and college student son-in-law Tomoma. Reiko masturbating in a Japanese-style room. His son, Tomoma, is walking down the corridor and happens to see the scene. At dinner, Tomoma makes up his mind to say that he saw his mother masturbate, and he gets angry that he can't do anything because he's worried about Reiko. After having sex with her husband, Reiko becomes concerned about her son and enters Tomoma's room. My son, Tomoma, who suddenly asks me to hug him. Although Reiko is confused, she accepts SEX with such a son.