Where did it all go wrong? Was it the moment she dared to fall for Gu Jeheon, the only son of her sponsor? Or when she gave up her life as a pianist and gave birth to his child all alone? To raise the child of her first love by herself, Yeonjae abandons everything and runs away. But five years later, her first love suddenly reappears. While Yeonjae desperately tries to hide their child's existence, Jeheon finds himself drawn to her once again. Their unfinished relationship begins anew—this time, with a child who bears a striking resemblance to them both.