Momoko was proud of her son Kosuke, who was an excellent student unlike his father. However, her joy was crushed by a letter that revealed the fact that he had been switched at birth. Momoko was saddened, but she also came to terms with the confusion of having secretly seen him as a man... Kosuke was shocked to learn the truth, but he confessed the pain of having been aware of his mother as a woman. And so, in the rain, the two of them, soaking wet, passionately sought each other...