New answers tagged races
Beyond the (excellent) suggestion of just making her an actual cat, you could perhaps make her a more normal character who has blessing (or curse?) that either allows her to change form at will -- or perhaps occasionally against her will. (E.g. at night she's a cat, or any time she gets wet, or any time somebody speaks a certain phrase....) A bit of clever ...
Everyone's overlooking a rather oddball race originally put out in Dragon Magazine... the Tibbit. They are size small humanoids that can transform into house cats (make great rogues and sorcerers!).
These are, indeed, dracotaurs. They were published in D&D 3.5's Monster Manual 3. An excerpt from it with their description can be found here. They're also present in D&D 4e's MM2 as drakkoths.
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