She is a student of Oso Girl's Academy who gets involved in the murder case related to Ouryou Rikako and seems to be aware of what's going on around campus. She is Kagami's friend and classmate.
In the final episode, she becomes an inspector, working with Akane Tsunemori as the new junior inspector, with a first day on the job mirroring Tsunemori's own first day.
She's becoming a main character in the second season.