Ten years into her marriage, Momoko finds herself troubled by her relationship with her husband. At a long-awaited class reunion, she reunites with Yamashita, with whom she once had a romantic relationship. Now living alone due to a work transfer, Yamashita shares Momoko's loneliness, and as the drinking party progresses, their emotional distance quickly closes. After seeing a drunken Momoko home, Yamashita gives in to his pent-up feelings and pulls her into an embrace. Drawn to his warmth, Momoko surrenders emotionally and physically, and the two plunge into a passionate affair.