Visual novel
Chouhi joins Kazuto along with Kan'u after the two discover him together. Unlike Kan'u, who holds a more reserved Master-servant-like relationship with Kazuto, she treats Kazuto like an older sibling and calls him "big brother," similar to how she treats Kan'u. As a powerful character, Chouhi has the strongest Damage ability when used as a general in the game. However, she has no defense technique when used as a commander, thus making her unfit to be one.

Anime
Chouhi is a talkative and always cheerful girl. Although she is small and very smart in some things, she is naive in others, yet very powerful and strong, capable of competing against Kan'u in armed melee combat. She is one of the main characters and the first person to join Kan'u. Chouhi will also be very dedicated to her duty no matter what the cost to her (in one episode, for example, she fights bandits despite having a cold.) During the second season, she was opposed of Ryūbi of becoming Kan'u little sister as Chouhi was already made a vow with Kan'u to be her little sister but accepted when Ryūbi decides to make Kan'u her little sister instead. By the third season, she has accepted Ryūbi as her other older sister and even calling her Touka-neechan. She wears a hairpin in the shape of a round yellow "smiley face" that changes expressions according to Chouhi's mood.

Before she joined Kan'u, she was a leader of a kids bandit group called Rin Rin Bandits. The reason she made that group was so she wouldnt feel alone. When she was very young, a group of bandits killed her parents and was taken in by her grandfather. But when he passed away, she was all alone, until she met Kan'u.

She only approves her friends and family to call her Rin Rin, her real name.

(Source: Wikipedia)