In the final days of war, Kayo lost everything to the flames of battle, left with only her son, Shunichi, to survive. She later remarried, building a new life with her current husband. Shunichi, devoted to his mother, studied hard and grew into an outstanding young man. But Kayo suffers daily abuse at the hands of her husband, weeping in silence. One day, Shunichi learns the tragic truth of his mother's past, just as he receives his draft notice to the battlefield. For the first time, he feels a father's tenderness. In the bath one night, Kayo gently washes Shunichi's body, sharing warmth and comfort. The husband silently looks away. That night, a forbidden act takes place.