They look so cute together. Since this is a form of chibi art, I will not go into proper proportion, but the girls back leg and foot look odd, as if she has almost a peg leg and not much of a foot there. Placing some shadows and highlights will really make your art pop, as they are now they are rather flat and lifeless looking. Use different colors when doing hair as it is not all one color and remember to place a cast shadow to marry them to the background, so they don't look like they are floating in space. Very cute, thanks for sharing.