Norimitsu Kaihō is a Japanese light novel writer, manga author, and anime screenwriter born in Kanagawa Prefecture. He is a graduate of Keio University, where he was a member of the university's Fantasy Study Group. His early career was marked by his involvement in translating English-language tabletop role-playing games and American comics, including working on the translation team for the role-playing game TORG and later contributing to Japanese editions of titles such as X-Men and Watchmen. This background in translation and his deep engagement with speculative fiction laid the foundation for his subsequent work as a creator of original stories across multiple media.

Kaihō is perhaps best known as the original creator and primary writer of the manga and anime series School-Live!, also known as Gakkō Gurashi!. The manga, illustrated by Sadoru Chiba, was serialized in Houbunsha's Manga Time Kirara Forward magazine from May 2012 to November 2019, spanning twelve volumes. The story follows a group of high school girls who are members of the School Living Club, living within their school building while a zombie apocalypse has ravaged the outside world. The series is noted for its deceptive initial presentation as a lighthearted slice-of-life story before revealing its darker horror elements. Kaihō also wrote a sequel manga, School-Live! Letters, which was serialized from 2020 to 2021. For the twelve-episode anime adaptation of School-Live! produced by Lerche and broadcast in 2015, Kaihō personally handled the series composition and wrote several of the scripts, ensuring a direct creative link between the original manga and its animated version.

Beyond School-Live!, Kaihō has established a significant presence in the anime industry as a screenwriter and series composer. He collaborated closely with writer Kazutaka Kodaka on several high-profile projects. He was responsible for adapting Kodaka's original plot into the television anime Danganronpa 3: The End of Hope's Peak High School, which aired in 2016. He later worked with Kodaka again as the screenwriter for the original cyberpunk action anime Akudama Drive, which aired in 2020. His work on Akudama Drive earned him the Best in Original Screenplay award in an Anime Trending poll. Kaihō's other notable anime credits include providing the script for the series Magical Girl Special Ops Asuka in 2019 and contributing as a scriptwriter for Astra Lost in Space in the same year. He served as a writer for the original anime Giant Beasts of Ars in 2023.

Kaihō has a long-standing association with the Guilty Gear fighting game franchise. He wrote the story modes for several games, including the home versions of Guilty Gear X and Guilty Gear XX, as well as Guilty Gear 2 Overture. He also authored novels and drama CDs based on the series and provided the original draft for the Guilty Gear Xtra manga. In 2024, it was announced that he would be involved in the upcoming Guilty Gear Strive: Dual Rulers anime television series, where he is credited with series composition and screenplay.

As a writer, Kaihō is often associated with Nitroplus, a company known for producing visual novels and anime with dark or complex narratives. His work frequently explores the juxtaposition of ordinary, often cheerful, daily life with sudden, brutal, or catastrophic circumstances, a theme most evident in the genre-twisting premise of School-Live!. He is also known for his ability to work within established fictional universes, such as Guilty Gear and Danganronpa, while also being a driving force behind original creations. His career demonstrates a versatile command of different media, moving fluidly between manga, novels, anime screenplays, and game scenarios, which has made him a notable figure in contemporary Japanese pop culture storytelling.