Dr. Moriarty

Dr. Moriarty is Sherlock Holmes's nemesis.

History
Lisa said to Bart that she thought he needed Skinner as everybody needs a nemesis. Sherlock Holmes had his Dr. Moriarty, Mountain Dew has its Mellow Yellow and even Maggie has that baby with the one eyebrow.

Behind the Laughter
Although named Dr. Moriarty, in the Sherlock Holmes novels, he is actually a professor.