I think you did very well for painting something you wouldn't normally paint. I feel like this is a nice improvement over some of your other drawings, too! The main thing I wanted to give some advice on is to watch your anatomy, you've lost the neck entirely on the blonde woman's body. Form your line drawing I can see that you originally drew the shoulder there, but it didn't translate well in the end. Keep in mind that the shoulders are really the top of the body, aside from the neck and you're not going to really have that excess above them going towards the head.
I think the problem also arises from an incorrectly placed shoulder as well. What I'm about to say is a very important piece of advice: try and make the gestures and positions you're drawing with your own body, and if it's painful to contort that way, keep that in mind when you're drawing your gestures. If you were to draw a box in perspective around the blonde woman's hips, and then to draw another one around her chest and back, you would find that she's been twisted at an unrealistic angle. This goes for the feet and legs as well.
I find the color scheme to be quite pleasing and I enjoy the symbolism you've injected it with. What I would have loved to see was a greater use of value in this picture, darker dark values, namely. A good tip is to put your picture under a black and white filter and see if the picture has a good balance. I can see already from what you've done that you've made the two people the darkest ones, but I'd like to see that taken to a heightened level.