The story of 18-year-old high school seniors. The newcomer Chun-u behaves modestly and has not befriended anyone yet. The life of his classmate Su-bin is completely dictated by her mother, but after meeting Chun-u, the girl begins to dream of escaping from her overprotective mother. The handsome Hwi-yeon pretends to be confident, but in reality the guy is driven by his fears and insecurities.