She is 15 years old when the series begins, Nanoka is a bright and active girl, largely typical of her age group. She is attached to her newly-rediscovered older brother, and is easily annoyed with his brusqueness. Her friends periodically tease her about having a "brother complex", which has more truth than she's willing to admit to anyone besides herself.

Spoiler

Ironically, she comes to terms with her feelings for her brother before he does.