High School Conquest: War Against the Bullies

Doyul, son of the world's top assassin organization leader, transfers to a Korean high school! Arriving as a penniless transfer student, Doyul takes on a request from Dong-gu, a victim of school violence, and starts taking down the surrounding bullies one by one! The story of a man becoming the strongest in the school world!

(Source: Naver Corporation, translated)