Woo Jia is the younger sister to Ji-ho (Zico) and Ji-seok (Taewoon), but she is way more shy than them. She doesn't have many friends because of that. Ji-ho is well known in the underground rap scene and takes his sister and his friend, Kyung, to some of his performances. At one of the performances, Jia meets Mino and he gets interested in her after the one encounter. So, he starts to do everything he can to win her over.