Bokaksaeng

Cheol Im was known for his strength in middle school before dropping out. Years later, he discovers that his childhood friend, Sol Kim, was killed by bullies. Seeking revenge, he enrolls back in the school. However, his plan is complicated when Ha-yun Seo, an orphan who was close to him, becomes a teacher there. He must now decide whether to pursue vengeance or stand by the person who once looked out for him.