Kenji Inoue is a Japanese author and manga creator, born in 1980 in Tokyo and raised in Sapporo, Hokkaido. He began his career as a writer when his debut light novel, Baka and Test - Summon the Beasts, received an Editor's Special Award at the 8th Entame Awards in 2006. This work marked his official entry into the publishing industry and became a significant commercial success, with the series ranking first in the 2010 edition of the light novel guide Kono Light Novel ga Sugoi!. The original Baka and Test light novel series was published by Famiou Bunko and ran from 2007 to 2015, spanning twelve main volumes and six short story collections.

Inoue is best known as the original creator behind two major comedy franchises. The first is Baka and Test - Summon the Beasts, which was adapted into multiple anime television series. The first season aired in 2010, followed by a second season, as well as an OVA special collection that continues the story. The anime adaptations were produced by Media Factory and distributed in English by FUNimation Productions. Inoue is credited as the original story creator for all these animated versions.

His second major work is the manga Grand Blue Dreaming, which he writes while illustrator Kimitake Yoshioka handles the artwork. The series began serialization in Kodansha's seinen manga magazine Good! Afternoon in April 2014 and remains ongoing. The manga has been adapted into an anime television series that first aired from July to September 2018, produced by studio Zero-G. A live-action film adaptation was released in August 2020, and a second anime season aired from July to September 2025, with a third season scheduled for July 2026. Inoue personally wrote the script for the ninth episode of the first anime season.

Beyond his original creations, Inoue has worked extensively as an anime screenwriter and series composer. Beginning in 2013, he collaborated with fellow writer Minato Hazuki on the scripts for the anime adaptation of Fate/kaleid liner Prisma Illya. He served as series composition writer and scriptwriter for multiple installments of this franchise, including the main seasons 2wei!, 2wei Herz!, and 3rei!!, as well as the theatrical films. This work marked his first professional role as an anime scriptwriter.

Inoue's creative identity is strongly associated with comedy, often blending absurd humor with elements of青春情味, a Japanese concept referring to the bittersweet sentimentality of youth. Both Baka and Test and Grand Blue Dreaming feature protagonists navigating school or college life while becoming entangled in chaotic, frequently humorous situations involving their peers. Thematically, his works often explore camaraderie, rivalry, and the comedic consequences of poor decision-making. Outside of writing, Inoue has disclosed that he also works as an industrial designer, a fact he mentioned in the afterword of the fifth volume of Baka and Test. This dual career path distinguishes him within the industry as a creator who maintained professional work outside of entertainment writing.