Tesche is a mean spirited teacher who is a overblown version of any bad teacher. He also likes to instate rules that contradict eachother (no raising your hands, no talking out of turn, must answer questions).
Tesche is obsessed with Triangles to a fault. In fact he refuses to teach anything else. One time he had a review sheet called "Ass Hole Squares" indicating that he probably hates Squares the most out of all non-triangle shapes.