/ic/ - Artwork/Critique

Can anyone help me with this? This is a rough sketch based on a previous one I did from imagination, I used a ref for the legs with this one. I want to know if someone can point out anatomical issues with it, something that looks wonky, not so much proportions (although these are welcomed) but things not being logical, anatomically impossible etc... If nothing else, tell me if I got the breasts okay, they are supposed to be a little squished by the gun, don't have a lot of practice with these kinds of stuff.

I know the rifle is shit, its just a placeholder, the full piece will get more attention to detail.

Thanks.