Nooo, Dave, you can't be something you already are! That defeats the whole point of Halloween!

[Since Dave is not providing helpful suggestions, Jade starts brainstorming out loud.]

What about... a princess super hero! Who has really cool magic, and wears one of those cute outfits like in the animes. And she has all kind of cool magic and abilities, and maybe also robot armor? Do we have time to make robot armor?