Marvelous work, as I already mention.
That are only things i could find scratchy - lower lip and unsmiley eyes.
Tried to edit - not good on faces though, might not be an improvement at all.

I guess you're still working on shapes and did not care about texture for now (robots are all about texture I guess even if I'm wrong=)) and unclean lining, so I won't comment on that part.
Tail might looks like that:



And in animation cycle (roughly, a lot depends on body movement=)



Also, just noticed - his side fin should be lower I guess. I'm not sure though.

Awesome piece =)

The only two things I woud fix - make lower lip bottom line less defined to the ends, now it feels that her lower lip a bit far foward then could be;
And lift eye brows a little up, it would give more girlish look.=)

Puppy for adoption.=)

fil_razorback, yeah, it's dragons shortage over there.

Eshaktaar, thanks for the point, I'll fix it when I'll get closer. It not a shapes are bothering me, i try to understand coloring, thats my favorite  pain in a butt. I feel I need dark low saturated tone for the deep shadow and i am out of it.