Kanade Yuuki悠木 かなで

Who is Kanade Yuuki?

Kanade is Kohei's childhood friend, and is the older sister of Haruna. She is constantly in high spirits, and likes to do things at her own pace. She loves her younger sister so much, that she says that if she had been born a man from another family, she would have definitely married Haruna eventually. She often calls her sister "Hina". She is shown to have feelings towards Kohei but doesn't accept it clearly nor denies it. In the OVA she tells Kohei is way better compared to Tsukasa.

Biography excerpt via Kitsu.