Trying to find a TF story

[Sabretooth]

Hey I'm trying to find an old TF story if anyone can be of any help. I *think* it takes place at a high school where two bully girls mess with a girl who turns out to be a witch. The main bully girl ends up turning into either a donkey or cow (as a result of a "cow" or "ass" trigger word she said being used against her), and secondary bully girl ends up turning into a dog as a result of the trigger word "bitch" being used against her. Any ideas, anyone?