RiN is a magical soldier locked in a perpetual war against the Yuragi, solitary demonic entities known for their brutal acts against humanity. She fights alongside her companions, Ai and Meg, facing an even greater threat when these creatures organize under a powerful leader.

She has brown hair cut to shoulder length and blue eyes. Her magical attire consists of a hair bow, stockings, and detached sleeves. In battle, she is frequently seen wielding a sword.

Her history is marked by a traumatic, non-consensual encounter with a powerful Yuragi named Shin, which resulted in the birth of her daughter, Mayu. Shin later uses their daughter in his scheme to create a paradise for his species, an act that forces RiN into a direct confrontation with him and his plans.

Her ongoing role is one of continuous combat as part of a team, dedicated to thwarting Shin's objectives and the Yuragi threat.