Thanx thats what i was thinking aswell. About her not being lit. My lighting setup needs work. Right now im using an SB600 and my on camera flash on my d80. I will also look into the makeup any tips on that?
Usually when I see photos of a girl in lingerie on a hotel bed, I don't think of composition, but in your case I'll try and keep my mind in a clean state
From what I hear, a studio strobe with a softbox will make TONS of difference in your lighting. I know you don't have one, but just keep in mind some of the more "professional" looking shots you see will be using these sorts of methods of lighting. You can only provide so much soft, flattering light with a 2 square inch flash
The white balance is off (easy fix), and the light in the background of the third shot is kind of messing with the exposure. If I were you, I'd reshoot the whole thing, if for no reason than to get her to put the skirt back on. I know its horrible to have to get a hot chick to put on sexy lingerie and pose seductively for you, but try and manage

I would then try putting something like a few pieces of toilet paper in front of your flash to soften it (I know its ghetto, but it works). And then, I'd adjust my white balance, turn off the table lights, and go from there. And most importantly, have fun (which shouldn't be to difficult)!
Edited to add: I don't want to say you SHOULD do this, but I would play around with taking out the crease between her booty and thigh in the third. I don't mind it, and I don't think anyone else really would, but your model might. Women get REALLY finicky about their thighs, and you might want to get rid of it if she thinks its not flattering. But it might make her look funny without it, and she also may not care. In either respect, I would leave it as is.