Ranran, a beautiful housewife entering her fourth year of marriage. She's a perfect homemaker, with spotless cleaning, perfectly balanced meals, and everything else done to perfection. However, the strain of housework has worsened her back pain, leading her husband to suggest calling a visiting masseur. Despite not finding the masseur physically appealing, she finds herself succumbing to his skills and compatibility during a midday session at home, alone with him, falling deep into the forbidden waters of adultery.