Каґурадзака Ері

An English teacher at Jindai High and is the class advisor to Sousuke, Kaname, Kyoko, Shinji and Mizuki at Class II-4. She is a kind and understanding teacher, who is willing to put the interest of her students over her own, as shown when she confronted Gauron and some North Korean secret agents over taking Kaname from her seat in the hijacked Boeing 747 in Sunan Air Base. However, she's known to get a mean temper whenever she finds Sousuke to be responsible for disastrous things in the school (which she always is a victim of). (From Wikipedia)