Toru Shirogane is a Japanese author recognized as the original creator of the light novel series The Kept Man of the Princess Knight. The series began publication under ASCII Media Works' Dengeki Bunko imprint in February 2022, with illustrations by Saki Mashima. Prior to its publication, the manuscript won the Grand Prize at the 28th Dengeki Novel Prize in 2021.

As the author of the original work, Shirogane is also credited for the story of the subsequent manga adaptation, which began serialization in September 2022 on Kadokawa's ComicWalker website with illustrations by Keyyang. An anime television series adaptation was announced in February 2025. The series is licensed for English release in both light novel and manga formats by Yen Press.

The creator's body of work primarily centers on this single series, which blends high fantasy and noir elements within a narrative that subverts traditional isekai and adventure tropes. The story follows Matthew, a seemingly worthless drifter who secretly operates in the shadows to support Princess Knight Alwin, a warrior seeking to restore her fallen kingdom. This dynamic, focusing on a protagonist who serves as a hidden asset to a capable heroine, establishes a recurring theme of contrasting public perception with concealed competence.