Takaya Kagami is a Japanese novelist and manga original creator born on May 22, 1979, in Tokyo. Initially aspiring to become a doctor, his family became involved in a land speculation issue during his high school years, leading him to drop out of school. He later earned his high school equivalency and began writing fiction around the age of 20. His professional debut came in 2000 when his work was selected as a semi-finalist for the 12th Fantasia Long Novel Grand Prize.

Kagami’s career is defined by a series of commercially successful light novel series that have been adapted into manga and anime. One of his earliest major works is The Legend of the Legendary Heroes, a fantasy series published under the Fujimi Fantasia Bunko imprint with illustrations by Saori Toyota. The franchise expanded into multiple manga adaptations and a 24-episode anime television series produced by ZEXCS in 2010.

Another significant work is Itsuka Tenma no Kuro Usagi, known in English as A Dark Rabbit Has Seven Lives. This series, illustrated by Yu Kamiya, was published between 2008 and 2013, spanning 18 volumes. It was adapted into a 12-episode anime in 2011, also produced by ZEXCS, as well as several manga series.

Kagami is also widely recognized for Owari no Seraph, or Seraph of the End. This project began as a large-scale collaboration, with Kagami as the original creator and scriptwriter, Yamato Yamamoto providing the art, and Daisuke Furuya assisting with story composition. The manga launched in 2012, and a prequel light novel series, illustrated by Yamamoto, followed. The franchise achieved significant international popularity, leading to a two-part anime adaptation produced by WIT Studio in 2015.

Across his body of work, recurring themes include intense friendships, often between male protagonists, who are bound by sacrifice and mutual protection. His stories frequently feature protagonists burdened with immense, often hidden, powers and complex world-building involving curses, political intrigue, and non-human entities such as demons and vampires. This thematic consistency, combined with a rapid publication schedule that has seen multiple series running concurrently, has established Kagami as a prolific and commercially significant figure in the light novel and manga industries. His series are noted for their substantial length, with The Legend of the Legendary Heroes saga comprising over 40 volumes across its main story and side stories.