Jung Haru is a new teacher at Hanuel Elite School in Seoul, a school for wealthy and top-performing students. Jung Haru is a quiet, kind, sweet, 27-year-old, innocent, and comes from a poor family. And he doesn't know that something bad is waiting for him. He became the new homeroom teacher for class 3-A, the most outstanding class, and there was a student who was the smartest and most feared in that class. He walked into class 3-A with a sweet smile and introduced himself.

"Hi, good morning everyone, I am Jung Haru, the new homeroom teacher of this class."