Koruri Masaki is a character in the anime Libra of Nil Admirari. She is a trainee reporter who attended the same all‑girls school as Tsugumi Kuze, the protagonist, and was one year senior to her. The two became good friends during that time. Koruri is a young woman of twenty years with short brown hair and golden eyes. Her background as a student and aspiring journalist gives her a connection to ordinary life outside the mystery surrounding the cursed books called Maremono. Her motivation appears to stem primarily from loyalty to Tsugumi and a reporter’s desire to uncover the truth. In the story, she acts as a supportive friend and occasionally offers a civilian perspective on the strange events. Her relationship with Tsugumi is the most developed; she also interacts with other members of the Imperial Library Information Management Bureau, though her everyday upbringing contrasts with their involvement in the supernatural. Information about Koruri’s personal development over the course of the narrative is limited, but her role as a steadfast ally and her commitment to her friend remain consistent throughout. No special abilities related to the Maremono are depicted for her.