This is very well done. I was impressed how it conveys weight and anatomy very accurately.

I noticed the shading on the face, which conveys the 3D structure of the brow with a minimum of lines or color variation.

The right pectoral area is very good; the breast has realistic weight, the tendon insertion of the pectoralis is well done and not neglected (most artists focus of boob drawing and forget the underlying musculature entirely).

Similarly the right upper arm is great. You can see her engaging the biceps to pronate the arm and the triceps to extend it. This gives her a feeling of activity, like she's ready to push off from the seated position and stand up at any moment.

The indents on the right leg as it rests on the left leg are perfect.

Trivial suggestions given only because you're so close on the anatomy and I suspect you are working on your figure drawing: the right deltoid is a little off. The position of the clavicles is subtly off. Also with her head in that position the sternocleidomastoid should be engaged; we should see a hint of this muscle above the clavicle going diagonally up the base of the neck.