Hi grundalug,
I like the idea of the demon dude offering something. especially the face looks convincing to me and you put a lot of work into it. good work :>
I made a little overpaint
http://i.imgur.com/Wx2vo.jpg
on the left the original image, in the middle the stuff i've added, on the right the new image.
i think it would be better to make him look at the viewer, atm he is looking of the page and that is where the eye of the beholder will go, unless there is something catching it, which there isnt. also is that fire coming from his hands? if it is you should add more lighting. I enhanced the blue light you have coming from the right and I tried to push some off the things down a bit (espacially the latch on his coat). but thats all details, all in all it is really good.
what you could try would be to make the narrative stronger by having him making a "let's shake hands"-gesture. atm he is more like: check out my cool smoke-trick. I hope that makes sense ^^
cheers,
flo