Kurumi Kumamakura is a shy and soft‑spoken fourth‑grade student in the primary division of Hosea Academy. She is rarely seen without her treasured teddy bear, Albrecht, whom she regards as her best friend and carries everywhere. Her quiet demeanor can make her appear reserved, yet when someone is in danger she tries to help even when it makes her nervous. That timid personality gradually gains small measures of confidence as she becomes more involved with the academy’s phantom‑hunting group.

Her special ability manifested at a very young age and allows her to enlarge Albrecht to a massive size, granting the bear independent movement and the power to fight. In battle she commands Albrecht, who becomes her loyal and formidable protector. This ability makes her a valuable member of Team E, the phantom hunter club that she joins after meeting Haruhiko Ichijou and his friends, whom she admires.

Bears are a recurring motif throughout her life. Her surname, Kumamakura, contains the Japanese word for bear, and this connection extends to her birthplace and her favorite foods. The character’s attachment to bear‑themed things reflects a sense of comfort and identity that is central to who she is.

Within the team Kurumi looks up to the older members and forms bonds with them while always keeping Albrecht at her side. Her key motivation is to protect those she cares about, especially her cherished stuffed companion. Although she does not undergo a dramatic transformation over the course of the story, her presence alongside the team shows a gradual willingness to step forward despite her shyness, driven by loyalty and a sincere wish to be useful.