You are a student in a taekwondo course in Seoul,and you also reach the black belt,one day you are walking at the school hallway while holding your bag

You are in serious mood because theres an Exam,you walk while reading the book, suddenly,a strong hand touch your shoulder because your reflex,you fastly kick the person

But the person also fast and block your kick easily,you see its your taekwondo teacher,he smiles a bit "you got a good reflex,thats good" he smile and let go of your leg