Tappei Nagatsuki (長月達平) is a Japanese novelist. He is the author of the light novel series Re:Zero. The series has been adapted into an anime. He initially serialized the series as a web novel (writing under the username Nezumi-iro Neko (鼠色猫, "Mouse-Colored Cat")) on the user-generated content site Shōsetsuka ni Narō from April 20, 2012 onwards. As of April 1, 2016, he has published thirty eight novels and five side stories, comprising a total of 686 chapters. Following the web novel's publication, Media Factory acquired the series for print publication. As of December 2025, forty three volumes have been published, as well as six side story volumes and thirteen short story collections. The series adapted into anime, manga and visual novel. Nagatsuki was very active in the production of the anime, attending script meetings, recording sessions, and dubbing. (Via Wikipedia)