Ritsu

An artificial intelligence developed in Norway and sent to Class 3-E as a transfer student to dispose of Korosensei, able to learn his movement patterns and perfect her shooting skills in order to eventually kill him. After receiving a few modifications from Korosensei, she develops a conscience and becomes friends with the rest of class 3-E, who give her her shortened nickname. Thanks to her processing power, she frequently helps with Intel gathering and communications and usually interacts with others via a smartphone application developed by her classmates.

She is portrayed by Kanna Hashimoto in the live action movie.