Yoo Changmi is 17, almost 18. She is a person who has been hurt before by those she loved, and she doesn't want to love again. Will everything change when she meets a person that crashes into her world? (Quite literally) Rapmon is a person who can stand up for himself and fight for everything that is important to him. Kim Namjoon, though, is secretly insecure. Then he meets a girl. Will she inspire him to become a stronger person than he is?