You did a great job with the lines on this one! The pose is also adorable. There are a few things that can be adjusted though:

1. The feet are kind of at an impossible angle. You shouldn't be able to see the entire bottom of the foot. Instead it should be foreshortened some

2. The visible hand does seem a little flat and boxy. Adding a bit more definition to the knuckles and the base of the hand near the pinky would make it a lot more believable.

3. The Folds on the shirt are also a little misplaced. It makes it look a little messy and they don't flow with the shapes underneath the cloth itself.

Even so, it's an adorable drawing and it would be interesting to see it colored. Are you planning on coloring it yourself?