Momoko had always taken pride in her son Kosuke, who excelled academically despite not taking after his parents. But her joy was shattered by a letter revealing the shocking truth: he had been switched at birth. Amid her sorrow, Momoko realized she had begun seeing him as a man, and she struggled with this conflicting emotion. Meanwhile, Kosuke, upon learning the truth, recognized his growing attraction toward her as a woman and confessed his inner turmoil. On a rainy day, drenched and vulnerable, they gave in to their feelings. Opening up to each other, they forged a new relationship. As emotions ran high, their bond grew deeper than ever.