Yoriko Matsumoto

The girls' homeroom teacher and advisor of the Data Processing Club. She is often called "Mom" (お母さん Okaa-san) by her students due to her generally kind nature. Yui, Yuzuko and Yukari in the Data Processing Club are fascinated by her large breasts and like to play tricks on her. She is always very polite about it and never seems to mind too much.