From ADV:

Woo Sang High is under attack! The entire student body is being terrorized by a duo of frightening bullies who have recently been released from a juvenile detention center. Guk Do and his muscle-headed sidekick, Chung Ki, are on a rampage and they have set their sights on Saang Tae, a brawny teenager with the courage of ten men. He alone will battle the fearsome duo, but there’s only room for a few at the top, and only one man can be The Boss.