Yoo‑yeong, a girl who had been left alone in a rundown apartment since the age of fourteen. One day, she finds an eight‑year‑old boy named Sian sitting alone on the stairs, as if he had been abandoned. Unable to turn away from a child who reminded her of herself, Yoo‑yeong takes Sian home. The two gradually become each other's only family in the world. "What do I have to do to marry you, noona?" "When you grow up, get into Harvard as the top student — and graduate at the top too." It was just a joke she made to a child. It was clearly just a joke...