Kaho and Ichiro began dating as students and married two years ago, remaining a loving couple until Ichiro’s affair came to light that summer. Their unsuccessful attempts to conceive leave Kaho devastated. Around that time, Ichiro’s father Toru stays with them during a business trip to Tokyo. Reunited with the father-in-law who had always treated her kindly, Kaho finds herself increasingly drawn to him. Once she realizes she has been subtly seducing Toru, she makes up her mind and heads to his home.