White
Nessarose gazes at herself in the mirror, admiring her stockings. They are blue and white, contrasting nicely with her shoes.
She's heard that white is the color of witches, and she sometimes considers herself to be one. The Wicked Witch of the East, they call her.
If she is a witch like she thinks, she must be a wicked one, like they say.
For wicked witches wear white sparingly, on little things like hairpins and stockings. Good witches wear white all the time, on their dresses, on their shoes, their eyeshadow.
She supposes good witches are boring, like the color white.