Not bad! The clothes look pretty good and I like the expressions. What I think you could improve on is the head structure; notice that their head look a bit stretched/slanted. This could have happened it you didn't draw it on a table or drew it looking at the page at an angle (I do that a lot lol). I've attached a visual critique to help you help you understand what the heck I'm talking about.
Otherwise, this is a pretty good drawing. I hope to see it finished soon!
Otherwise, this is a pretty good drawing. I hope to see it finished soon!
P.S. Gravitation!!