I'm so glad you went with the flames! I knew you could make it awesome!

(not that it wasn't already)

 WELP.

I suppose I'm required to revoke my previous comments!

 The hands are kind of unreadable, unless you meant the left hand of the demon to be a hoof?

 right feet of the angel looks weird ( too big maybe), but it's a pretty cool image 

 I woulda added a little orange at the base of the demoness' horns, possibly given her some hooves opposed to feet and perhaps added a little orange around the base of the eyes to bring out the luminosity a little more but that's just me. angel is spot on, no problems there except for the belly buttons as r1k pointed out, loving the transition of hair to flames, overall an awesome piece. favourited :)

I like the good/evil theme and the facial expressions that goes along with it.

4/5

... and, of course,  +1 for naked girls.

so, 5/5. :)

turned out great.  But one thing that really stands out to me is that the black on the angels belly button is too dark, given the low contrast you set up for the rest of the picture.