After losing his wife, the widowed father-in-law, Tohru, drowns himself in alcohol. Night after night, drunk and haunted by memories of his late wife's lips, he finds himself lost in longing. One evening, intoxicated and delirious, he sees a vision of his wife and instinctively moves in to kiss her—only to realize it's Kanako, his son's slender, married wife, who had come to check on him out of concern. From that moment, Kanako's lips linger in Tohru's mind. He sneaks into her room and forcefully claims her mouth, entwining his tongue with hers in a passionate, invasive kiss. Kanako, overwhelmed by the sensation, becomes addicted to the forbidden kisses, unable to suppress her own rising desire. As the line between fantasy and reality blurs, the secret affair between Tohru and Kanako deepens into an illicit bond of lust and emotional entanglement.