I had a mathematics teacher who was a total psychopath. If you gave him any cheek he would wait a couple of days and then he would be walking around the class nonchalantly and punch you in the back of the head. I happened to be watching him one day he did it to a kid a couple of seats along from me. I will never forget the look of pure evil he had on his face. I copped it a couple of times and I don't know why because butter wouldn't melt in my mouth.
