Sayumi lives an ordinary life with her husband and college-aged son. One day, she fails to lock the door to the bathroom and her son accidentally sees her. The son, however, is now conscious of his mother as a woman.... Then, on a hot and humid summer night, the son, unable to resist the sight of his mother in her light clothing, finally pushes her down and rapes her. From then on, an abnormal relationship between mother and son began...
