Arima Shouko

She is a classmate of Setsuna and she and her two friends (Satou and Mirozawa) regularly pick on Setsuna. However, this only covers up the fact that she has a crush on him (one that she has a hard time even admitting to herself). but will regularly revert to her angry persona when things don't go her way. She lives alone in an apartment (which she bought with her "pocket money", revealing that she is quite wealthy) because she can't stand her parents. She later becomes the master to the Oni Princess' cousin Hina after destroying a magical orb and saving Hina's life.