Kohei Izawa, president of Izawa Trading, seeks to break the monotony of his stagnant married life by spending more time at the office and experimenting with new toys. However, his efforts prove futile as his wife, Ryoko (Izawa), has already grown emotionally distant. Growing suspicious that she might be cheating, Kohei asks his secretary—and Ryoko's cousin—Nobuo to investigate. Nobuo, who harbors secret feelings for Ryoko, reluctantly agrees and begins surveillance on her home. One day, he discovers Ryoko bringing a young man into her room and engaging in intensely lewd acts, leaving him shocked and heartbroken as his idealized image of her comes crashing down.