The anatomy is very off, the arms, shoulders, boobs, torso and groin haven't clearly been thought out.
The biggest area for me is the bum, and side of her body to her groin, do me a favour, open this up in photoshop or whatever, get a red brush and line over the anatomy, I want you to point out where:
The belly button is
Her groin is
The biggest issue is, you're hiding what you don't know, and covering it up, it looks awkward!
I'll give this a red line at a later date if you need it, but do draw over it showing me where you think things are, so I can explain where you are going wrong.