If that's what you can do in an hour, I would love to see what you could do in a week, or a month. It really is well done, and if you were inconsistent with defining lines than I would probably say something about it, but it seems fine as it is in my opinion. Overall, very very well done for an hours work, great color usage and he has a strange look of a loyal dog for some reason.

I agree with Taco, it could have more defining lines to make the features of the demon to be more notorious to the eye, however the design is great hard to believe that this was all done in just one hour, did you have this guys already in mind before you started drawing him?

Also are there any chances of you revisiting this one in a future?

Quite honestly, this isn't bad for something done in an hour. It looks like it's quickly done as intended, but you can still find some details about it that seem to be good for the picture. And for being something done in such a limited time, it's actually fairly clean and well made. Only rating it a 4.5 since I personally think some details could be touched up some more, mainly lines separating parts of the demon's body, but that's just my opinion, really. Other than that, I like this a lot, great work.