Original by Woari at https://www.furaffinity.net/view/22967298/ Go comment there and tell them how much you like it!

This was an artistic liberty commission, based on a story. The details of the story developed with sketches, but here's where we ended:

Gilrandree is in the process of destroying a world, doing his demonic duty bringing down the Apocalypse. One of the smaller leaders (mayor of a mid-size town or similar) wants to save his people, so contacts the Demon of Deals (Glabrezu, who you see the back of) to negotiate on his behalf with Gil over what can be done to save that community.

We see those negotiations in progress; Gil is flanked by one of his priests (the manticore to his left) and two of his personal demons (the tauric beasts to either side, somewhere between wolf and lion). There are a couple of Hell Hounds on patrol as well, while Glabrezu stands there, almost protectively, over the human he's working on behalf of.
It was an intentional decision to put his (mortal) priest closer to Gil than the two actual demons in his service, and equally intentional that the two demons look slightly displeased at this fact.