Great
I think this one is pretty great in terms of your artistic ability and style. The demon like creature is just spot-on good and has eyes that draw you in. The background of small lines going into each other really helps you focus on the creature. It allows you to have full space and matches with the style of the creature. I love the horns and the way you did that a bit differently. The background color of grey is also fitting because it allows for some depth to this piece. I do think this one has potential for an animated short. I hope you'll do something like that. Good work overall, hope to see you start animating things similar to this soon.
~~THINGS TO IMPROVE ON~~
I do like it as is but maybe animate this one next time
~X~