Is the one on the left Tim Burton? The swirly motif and skinny, pointy features makes me think of Burton. Either way, this is a really good style emulation!

I also like the subtle plague doctor mask they have for a face. I almost didn't see it.

As for critique, I'm gonna focus on the shading. There's a bit of a pillow-shading issue, it'd look better to pick a direction for the lightsource. In this case, I'd pick upwards (so the shadowing would be on top), I think it'd work with the creepy characters. It's also generally a good idea to use a different color for shading (I will never say 'always do this' when it comes to art), or at least a darker shade of the main color. Like for his skin I could see blue or purple being used.

I'd recommend another brush for this too. Is this airbrush or dodge/burn? In any case, try to give the shading/light a solid color first (like with pen) and then blend it. I don't know what program you're using so I can specific what to blend with, but you probably know what brushes will do that.

I hope this helps!