That was a difficult one! Challenging perspective. You have it here as a C curve as if she was bending forwards. I see her torso as bending backwards in a C curve shape and the ribcage slightly twisting towards the arm that is reaching down. I may have pushed that curve a bit more than is true in my drawing, but I think that it should be more of a convex curve. You did a great job with the twists in the rest of your boxes. I really like the deformation in #15. Keep up the good work!

should do the others i suppose but having too much fun with this

You've got it! Nice work :)