Tabitha Felman had a tail. It wasn't the kind of tail you could see, but it was there just the same. Anytime one of the other kids would trip in the hall for no apparent reason or things would go flying off their desks or when Tabitha would yelp because a door closed too quickly behind her, it was most likely her tail that was to blame.
She kept it a secret from everyone, including her friends, but Reggie Bluthe figured it out on his own. He never admitted to Tabitha that he knew but he knew. For his part, Reggie was happy enough to sit alone in the corner of the class and stick his invisible snout into a good book. He wasn't about to tell.