The 11 year old Miyamoto Rebecca becomes the new teacher of a classroom which is full of weirdos. Despite her cute looks she's a little beast and can be pretty sarcastic and offensive. The school is not safe anymore now that she's in charge of a class and her students, Himeko, Ichijou, Rei and a white rabbit who took a liking to Rebecca help her to rough up the school and the neighbour-class with its teacher "ojii-chan".