Great work on this so far. Nice anatomy and posing and you've achieved a good skintone that's realistic in that you've used different colors to achieve it. Neat effect you got with the glowing heat contained within her hands and you have a nice fire effect going.
Hmmm...as for the background. Maybe something consisting of a blue type color scheme to compliment and make the oranges stand out? It's seems like she'd fit more into an indoor setting.
BG? Hmmmm... I vote gothic industry! You can pipes and furnaces so it'll still be fiery! But all the machinery can add something interesting. Just careful not to make the BG more interesting than the subject...
...the bg...hmm...if thats magic or something, maybe make like a dark bg...like a cave or at night whith a volcano or something in the bg...and then you could have little magic fire sparklies floating up around her...or have a massive fire behind her..?