Bang Yoona returns home to South Korea after years of studying music overseas. She is Hitman Bang's daughter, unknown to the world but well known in the music industry for being talented in producing, singing And dancing. BTS have no idea who this girl is yet other idols do. What happens when she finally meets BTS, the most popular boy group? huh? how can she not know them when her father was the one who created this band? And why is she living with them in their dorm? let's just wait and see which member or members might have a blossoming romance.