The National Association of Marlon Brando Look Alikes, is a group of people that look much alike as famous celebrity Marlon Brando

The National Man-Boy Love Association. They are a group of men, mostly over 30, who like to date/have sex with underage boys. They like to use historical "evidence" like how in ancient Greece, this sort of thing was tolerated, to try and support their movement. (They also like to take text from books, out of context, to support their movement, the author unaware of their doing so, thus making that author look bad.)

Many people don't even realize the group exists and assume it was something made up for that episode of "South Park", which unfortunately is false.