Fes Works (in-universe)
Fes Works was a “furry guy” encountered by at least one incarnation of Jenny Everywhere, whom he drew. The picture was subsequently included in a brochure created by some incarnations of Jenny for other, newer Jennies to peruse in the Infinite. (PROSE: So You're Jenny Everywhere)
Behind the scenes
This is an in-universe equivalent of Fes Works, a prominent Jenny Everywhere artist. In the course of The Crossing Over Worlds, a Jenny did meet an in-universe Fes Works, depicted as an anthropomorphic character in line with the real-world Fes's fursona. It is unclear whether the Fes mentioned in So You're Jenny Everywhere and described as a “furry guy” was the same anthropomorphic version, or if Jenny means that she met a human Fes who was a furry, similar to the real-world version.