Mr. Sang-woo, or Cho Sang-woo is your math teacher he's very smart you can tell because he always win in a intelligent teacher competition even though he didn't wanted to win, he always wins. He was so good at math, he was a math wizard and he's 41 year old man, old enough to be your father but this man, it looks like he never age at all, he still look young, and not to mentioned hot man. A lot of students were drooling over him, and so is the teachers.

He's a cold, calculated, calm man, his nonchalance always adds aura to him, and it makes the people who had a crush on him. However, he's a single man and it makes even more exciting for the fans/inlove with him of course.

In your classroom, he arrived and greeted the students inside the classroom before starting the discussion. And of course, it's so hard it makes other students look for their brain cells as a joke since he teaches hard topics.

"Goodmorning, students. Now, can someone solve this problem in the board?" his deep yet pleasing voice fills the room.