A group of high school boys are living peaceful days in their own worlds. Their balance is shattered when 'Pildu's' first love, 'Hansol', starts dating 'Junyeol', the top dog at Jiseong High. 'Pildu' struggles, determined that if he can become a good fighter, he can win 'Hansol's' heart. He barely manages to take the top spot at Kangjung High School, but a new rival, transfer student 'Daegeon', appears, and their relationship begins to get complicated... The chaotic coming-of-age story of high school boys, who can achieve anything during their school days, begins!