I did this for a Secret Santa who asked for an illustration of the dark fae from C. S. Friedman's Coldfire trilogy. When I took the request, I immediately thought of this scene, from chapter 25 of Black Sun Rising. I've wanted to illustrate it since I first read the books (fifteen years ago now?).
Deciding to forgo my usual method of drawing and then coloring the lineart, I actually painted this from the ground up (well, digitally--all hail Photoshop!). I started this in October, ran into a two-week dead spot in November around Thanksgiving when I couldn't figure out how to fit Damien (on the right) into the scene, and then finished it just last week, four days before the deadline.
And then I decided I was dissatisfied with it because it didn't feature the fae to the extent I felt it should to answer the prompt, so I whipped up another picture in about three hours that focused more on the dark fae, and submitted them both.
Still, this is probably the most elaborate thing I've ever done, and as an illustration of that scene (one of my favorites) from one of my favorite books, I'm more than pleased. And I'm very pleased with how the fae looks in it, even though it didn't answer the prompt to my satisfaction.