That faraway look in her eyes(kinda bulgy like) when she's trying to force out words to make one complete sentence. Or maybe the drool oozing down the side of her mouth or a combination of them both. And I can't forget those mismatched buttons that she always does up wrong on her snot stained blouse.
chomp chomp.. umm you said trait.. so that means it's something about their personality.. I'd say outgoing in and of itself ha ha :) because outgoing usually means funny, smart, charming personality yep :)