Murr Basler is a major supporting character in Vanitas no Carte. He is a mysterious, intelligent black cat who accompanies Noé Archiviste and plays an important role in the story as both a companion and a source of comic relief. Despite his small size, Murr often behaves with surprising awareness and insight, and his connection to Noé is deeper than it first appears. He is one of the series’ most distinctive characters, contributing to the mood, mystery, and charm of the narrative.