I understand what you mean but I think its just an experimentation thing you will find some very good unlikely backgrounds if you just think about it and try different things out.

Ah, you're definitely right, but I'm just wasn't sure what to do with the setting, so I decided to leave it blank. She's a military robot, but a military setting doesn't fit the picture quite right you know?

Very good art work but it needs a context to the figure and what they are showing, be it a war zone or a school room each would bring a different feel to it. If you use photo shop or similar I would suggest supplanting different backgrounds to see what gives the right feel for you. Also I think you will see the character of the picture change as you change the background. Some I would suggest is warzone, padded cell, playground, burn/war damaged playground, school with children colouring and santa. See how each different background gives it a different feel and makes it either more real or more sinister or even more hopeful.
Also dont take my comments too close to heart because well that is just my opinion and who the hell am I? exactly
Thanks for sharing your work with me Blackheart

It's on the back, where it should be, at least I think.

p90...like the assault rifle? This guy looks cool. But if he is a represention of that gun he needs to have the see-through clip some where...