Tsutomu Satou is a Japanese author best known as the original creator of the light novel series The Irregular at Magic High School. This series serves as the source material for the numerous anime adaptations and films listed, including The Irregular at Magic High School, The Honor Student at Magic High School, The Irregular at Magic High School The Movie: The Girl Who Summons the Stars, The Irregular at Magic High School: Reminiscence Arc, and the upcoming Mahōka Kōkō no Rettōsei: Yotsuba Keishō-hen.

Satou began writing the story that would become The Irregular at Magic High School on the user-generated web novel website Shōsetsuka ni Narō, where he serialized the work from October 2008 to March 2011. Following its online success, he entered into an agreement with publisher ASCII Media Works to release the series in a print light novel format under its Dengeki Bunko imprint. The first light novel volume was published in July 2011, featuring illustrations by artist Kana Ishida. The main light novel series concluded in September 2020 after thirty-two volumes. Satou subsequently launched a direct sequel series titled The Irregular at Magic High School: Magian Company in October 2020.

The anime adaptation history of Satous work is extensive. The first season of the television anime, produced by studio Madhouse, aired from April to September 2014. A feature film with an original story written by Satou, The Irregular at Magic High School The Movie: The Girl Who Summons the Stars, was released in Japan in June 2017. A second television season adapting the Visitor Arc was produced by studio Eight Bit and aired from October to December 2020. A spin-off television series titled The Honor Student at Magic High School, based on the manga adaptation of Satous original story, aired from July to September 2021. A television film adaptation of the Reminiscence Arc was broadcast in December 2021. A third season of the main anime aired in 2024. An anime film adapting the Yotsuba Succession Arc has been announced for a 2026 premiere.

Beyond his primary role as a novelist, Satous authorship is the foundation for the entire franchise. The series is set in an alternate 2090s where magic is a systematized technology, and follows siblings Tatsuya and Miyuki Shiba as they navigate the social hierarchies of a magic high school while concealing their connections to the powerful Yotsuba clan. The franchise has been localized for English-speaking markets by Yen Press, which publishes both the original light novels and the various manga adaptations.