Age: 19
Birthday: October 15
Height: 170cm
Blood type: A
Zodiac: Libra

Kou is a friend of Hirotaka's little brother Nao. She has always been a loner playing video games until Nao approached her and asked her to teach him play a game Kou plays. Since she has been a loner for a long time, she gets shy every time Nao talks to her and has a tendency to apologize even though she didn't have to apologize for anything.

She gets easily mistaken for a boy since she dresses like one. It's unclear if Nao knows the fact that she is a girl.