I really like this idea. I find the conjunction of fixed jumping and tongue action to explore genuinely fun.
My only real gripe is, and I know what the theme is but, the controls are inconsistent in a way that make it feel very much not intentional. like sometimes it works really well with momentum and stuff, while other times I am fighting to get my tongue to stick to the surface it just stuck too.
Also my game consistently locking after beating level 5. no pause menu or clicking. only way to get out of it is to alt-f4.