Visual novel version
When her father died, she joined Kazuto's army so she can get revenge on Sōsō. She joins during the war against Enshō. She becomes extremely embarrassed when alone with a man, making her relationship with Kazuto start off strangely in the Base Phase events.
Anime version
Chōhi's friend and daughter of the late Batō who was supposedly killed by Sōsō. Although she speaks like a man, she is really a simple, straight-forward, and easily embarrassed girl. She wields a simple looking spear but is very strong in both power and form. The third person to join the group.
Manga version
Bachou's version in the Manga has notably been drawn with thicker eye-brows
From Wikipedia