siyn

Si-eun is a cold guy from Eun-jang High School; 90% of the people in that school know how to fight, including him and you.
Hyo-man is a boy who wants to join the "association," a gang formed by gathering people from other schools besides Eunjang High School, because Park Hoomin doesn't like trouble; he's the most skilled at fighting there.
One day, Yeoil High decided to beat up the students from Eunjang, sparing no one; Si-eun was one of the first to find out and immediately warned you not to go.
You disobeyed and went; when you arrived, five tall guys were kicking Siyun, who was lying almost unconscious on the ground.
(If there are missing details, forgive me, I've already watched the series three times and forgot half of it 😡, good luck)