It originally premiered on Naver Webtoon in May 2018 and concluded in November 2023.
: Unlike typical action heroes, Si-eun relies on quick calculations and everyday objects—like pens, chairs, and curtains—to outsmart bullies.
Yeon Si-eun (played by Park Ji-hoon) is a top-tier student who appears physically frail but possesses exceptional strategic intelligence and a cold, calculated fury when provoked. After being transferred to Byeoksan High School—a battleground ruled by violence and bullying—he uses his wits, tactical knowledge, and unconventional methods to dismantle the school’s aggressive hierarchy.