Nagasawa Mao

Nagasawa Ikki's little sister. Excels at her studies, cheerful, openhearted, and is popular at school. Always treats her big brother Ikki strictly, but she's very much aware that it's just the flip side of her love for Ikki. During that one time at the train, Mao actively went on the offensive against her brother. She's a pervert with an exhibitionist fetish. When around others and even her parents, she can't be upfront with her feelings, but when alone with her brother, she becomes gentle and sweet.

When in her "tsun" mode, she calls Ikki "Nii-san", and when in her "dere" mode, she calls him "Onii-chan".