Ryo has spent five modest but happy years married to Tetsugaku, a salesman. One day, while her husband is away, his boss Saji visits and claims that Tetsugaku made a costly mistake at work. He then pressures the bewildered Ryo into becoming his slave. She offers him her body to protect her husband, but the anal training that begins that day brings her pleasure and humiliation unlike anything she has ever felt. Her self-control slowly crumbles until she is spreading her asshole wide and cumming over and over...