Well, that's no ordinary dragon!
That's the most foul, cruel, and bad-tempered rodent you ever set eyes on!
(edit)
Well okay, constructive! If you move the eyes up a bit, they will look creepier. And just a bit of downturned line at the end of the mouth would give him a sinister sneer instead of the faux-smile.
The backward turned legs are kind of disturbing already, too.
