Great stuff in your longer and more sustained pose in the nude, MorganWant. Very good job on your gesture and life in the lines. Excellent placement of the anatomy of the legs and kneecaps.
If you wanna really get improving the most, then I'd recommend you this link right here. It's on how to draw gesture drawings, and it's universally applicable to your anatomy studies and any drawing and painting study there is. I really want you to download the images, then bookmark and reading list the images, and later, duplicate and print out your images for you to study them for 1 1/2 hours of 30 second poses in drawing.(90 minutes x 60 seconds=5400 seconds/30 secs=180 sketches)
The reason why you could and should do this improvement idea is, if you do this long and entertaining quick sketching of the poses, then you'd be able to get your myelin moving in your lines of action and of rhythm.
Your figure drawing looks great! You did quite well with the body's anatomy, but there are always things to improve on. For this specific drawing, I see 3 major issues, which are:
The hand: The hand that you drew seems to be a little too small and how it's placed on the chair looks kind of awkward. For the size of the hand, remember that it will always be the same size as the face and as for the position of the hand, I recommend looking at references on Pinterest or getting someone around you to try and replicate the pose and see how it looks then.
The chair: I get that the figure drawing was the part you were focusing on most, but if something around it is interacting with it, it should look good. I don't exactly know how to explain it, but the chair looks too unstable to hold up the person leaning on it, to be specific the top part of the chair. Either you could make it be like a normal chair with a full backrest or if you don't want to change it that much then try to make the lines there straighter and stable looking, some minor shading might help too.
The stylization: I can see that for this drawing you were going for a more realistic look, but sadly the face look a bit stylized, making it become a focal point for the viewers (which shouldn't be intended as the point of this drawing was the actual "figure drawing" part of it). The lips are what give away the stylization most in this, so try and make them less puffy. In general, just try and practice drawing more realistic side profiles and eventually it'll pay off in your full body drawings.
Other than these three points, I think you captured the flow and anatomy of the pose very well which is really hard once you get into the details so good job on that! And last but not least, happy drawing :)