Ghoon-Hahm Che
Only a first year in high school, he is the leader of the Yi Won gang and has a reputation to be a very tough individual. While in junior high school, he got into several fights where he was outnumbered, but ended up winning them anyway. He and Que-Min first met while still in elementary school and is also where Ghoon-Hahm developed his first crush on Que-Min. Source: Wikipedia