The husband is on an overseas assignment, leaving his mother-in-law Satomi and college student Yuichi to live together. One day, Satomi witnesses her sleeping son's erect penis. She can't resist her son's hard erection after being apart from her husband for so long, ultimately crossing the line. She takes in his throbbing penis and sucks greedily. In the house without her husband, their illicit lustful life together cannot be stopped.
