Okay I'm quite bad at explaining it so bear with me. This is something that after some doodling and thinking about it seemingly just happens
So the way I go about it is that the maw itself almost an afterthought
https://files.catbox.moe/hvz97i.jpgI first start with the actual body and just a very rough outline for the big mouth
And then I add details to both and the details on the maw are seemingly what gives most details
See the way that the teeth are shaped, his they curve together with the mouths curves
I think it's stuff like that that gives it a little more depth. Just leaning into the shapes and exaggerating them in a way
https://files.catbox.moe/qaw7hm.jpgAfter some details added we arrive at the end sketch
But to be very honest I don't spend very much time drawing these mawile doodles, since they are all very rough everywhere
I hope this helped somewhat
