It's the thumb! Length, girth, and shape of the thumb relates to the penis! *scrolls viciously through Marlon's pictures* Looks like it's average, but thick! Mmmm!

I bet anon, I bet. This is just, I don’t even know what to say… I’m going to grow a dick and see if your theory is right, but meanwhile you just keep scrolling viciously and doing your detective job :)