She first crossed the line with her adult son’s friend Yu five years ago. That night, after discovering her husband’s third affair and fighting bitterly with him, a devastated Yu comforted her and asked, “Why not use me to get revenge for his cheating?” Though Yu was portrayed as an adult student at the time and she felt guilty about sleeping with someone so much younger, she could not turn away from his feelings. Feeling a man’s warmth against her skin for the first time in years rekindled her desire, and the two continued meeting in secret for sex and creampies. But graduation and Yu’s departure bring changes to the world around them and to their five-year affair.