Lying Witch.
No need to insult witches, now. I happen to know some very nice (and very cute) witches, I will have you know. :)
Perhaps labeling her a muzrimmist would work better, as they also have no problems being deceitful to anyone who does not share the same beliefs as they do.
Indeed, they are quite gleeful about pulling the wool over everyone else’s eyes -just like mrs bill!