Chinatsu is stunned when her father-in-law suddenly appears in the bathroom. The man who has always been kind and understanding now does the unthinkable. Confused and helpless, Chinatsu is quickly cornered in the shower. "I've always dreamed of washing each other's backs like a real family," he says, as his rough fingers grope her full, soft breasts. In that moment, Chinatsu realizes her happy married life is over. Under the same roof in a dual-generation household, a forbidden relationship begins to twist the bonds of family, pulling them both into a whirlpool of illicit desire.