It's definitely an interesting piece! Great creativity, I can visualize this as an idea that someone would think is cool in their head... if that makes sense. Like when you just think of something and you HAVE to put it down, it makes me think of that original idea.
The skeleton's right forearm looks a little elongated. I'm not sure how far the elbow would actually go into space, but it's distracting. It makes my eyes follow the bones of the forearm right to the skull and then wonder where the elbow is.
The woman's breasts might be a little too upright? It feels like they should sag more to either side of her rib cage so they're not sat so firmly on top of her chest against the robe. I'm not sure what happened with the ridge of her hips, but it is severely misplaced. The left crest of her hip is much too high for where the far leg is placed. It looks like you wanted his forearm to be placed against her side so she's bent against it, but her mid-torso section is too straight.
Personally, I'd like a slightly different background? Some vague buildings, a tiny world, a sand oasis behind them so they're standing on some ledge as if she's been plucked from the earth. Context would be nice.
I love the vague halo! It's subtle.
Hope this helps!