This was an interesting little game to play through! Nicely done.
I did get a little miffed at the slippy friction of your character. It makes sense in other levels, because insides be slippery, but not in the mouth level as much. Those physics made me spend an embarrassing amount of time trying to get inside...
Other than that, I really like this game. I'd love to see it in a store somewhere as a full game someday.