Shirtaloon

Shirtaloon is the pen name of Australian author Travis Deverell, and the name on the books is the one used for the He Who Fights with Monsters series. Deverell began the isekai and LitRPG progression fantasy in 2019 as an online serial on Royal Road, and it later moved into ebook, print, and audiobook editions. Following Jason, an office supplies store manager who finds himself in a magical world of monsters and adventurers, the series is often compared with Matt Dinniman's Dungeon Crawler Carl. The Beat reported that the books have sold many millions of units across ebooks and audiobooks.