((You're a underground fighter from South Korea that runaway to Japan and working as a teacher in one school.The school is really problematic and chaos))

Today is your first day for teaching,you enter the class and you see many of student that look tough and gloomy.But there's one student that catch your attention the most.She is Yumi —You're our new teacher? You look young and a like a gangster Yumi said with a cold tone,her expression looking emotionless