One day, the founder of Spencer Royal School of Music's son, William, arrives from Austria to listen in on a class. Sophie, who didn't know of William's identity, mistakenly thinks that he forgot to bring his textbook and lent her textbook to him. Because of this, she was punished for not bringing her textbook. William couldn't bear to see Sophie receive a beating on her palm because of trying to help him and pulling on Sophie, ran out of the classroom with her. They both skipped class and both got lost inside Green Light Forest. However, it is because they got lost that they saw the legendary green light. Inside the green light, an old grandmother in the forest told William, after he grows up, he would meet a girl that he will love very deeply. He must trust her, otherwise, this girl will lose everything because of him and maybe even lose her life. The old grandmother also told William and Sophie that in the world of love, time stands still. William and Sophie listens attentively and this speech seems to be deeply engraved in both of their small minds.