Keita Uehara is the original creator behind the manga and subsequent anime adaptation of Anti-Hero Generations. His professional career began in the advertising industry, where he worked for approximately eight years before transitioning to a career as a manga artist. Prior to becoming a manga creator, his path also included periods as a copywriter, an art university student, and a designer. He is known as the author of the manga works Zowawa no Kamisama and About Hero.

Uehara gained wider recognition for his original manga Anti-Hero Generations, which won the grand prize in the New Generation YouTube Manga Award. This contest was organized by Plott, a Tokyo-based production company focused on creating and distributing manga and animation on YouTube, with the theme of selecting a work that could create a new era. The award included a cash prize and the promise of an anime adaptation. As a result, Uehara’s original manga was adapted into an original net animation (ONA) by Plott. The anime series premiered on YouTube in May 2022, with the theme song Tokyo Night Dive performed by the band KOTORI.

The story of Anti-Hero Generations is set in a Japan where giant monsters regularly appear and threaten lives. The protagonist, Kaneko, gets a job at a company that employs heroes to defeat these monsters. He soon discovers the truth that the company is secretly manufacturing the monsters and fixing the battles. Kaneko is then unexpectedly selected to pilot a monster, forcing him to confront questions about the nature and purpose of work. In a personal statement about the work, Uehara explained that he poured the conflicts he felt during his eight years in the advertising industry, as well as the answers he found to questions he could not fully resolve, into this narrative. He expressed a desire for anyone feeling insecure about their job or unable to face their work to see the anime.

Uehara's identity as a creator is deeply informed by his corporate experience, and his work often explores themes of labor, systemic hypocrisy, and individual purpose within a professional context. His journey from an advertising copywriter to an award-winning manga artist is a central part of his public profile. Anti-Hero Generations is significant as a notable example of a work that originated from a digital-first manga award and was produced for distribution on a streaming platform like YouTube, reflecting new pathways for original anime and manga production outside of traditional television and publishing models.