About Tharkis:
She's tiny.
She has a pair of kitty like fangs.
She wears her hair tied in twintails.
She wears glasses, usually rectangular half frame glasses that dont cover her whole eyes.
She wears a cat-bell collar frequently so the jingling makes sure she doesn't get run into or stepped on accidentally.
She gets flustered and upset when mistaken for a child, because she's a fully grown adult… just very small.