Ascendance of a Bookworm: Official Fanbook Volume 4 contains exclusive bonus content based on the series written by Miya Kazuki and illustrated by You Shiina and Suzuka.

Here is the fourth official Ascendance of a Bookworm fanbook, intended to be read after finishing Part 4 Volume 8 and Short Story Collection 1. This volume contains even more illustrations, character design sheets, and manga, as well as a short story not found in the light novels. Also included are exclusive notes about the development of the anime, design sheets for the gods, coverage of yet another drama CD, and a new extensive Q&A with author Miya Kazuki.