Seems to be a contradiction between the definition and the example of use.

It says that an ass-muppet is someone who likes to have ass-sex with muppets. Then the example says that Bert and Ernie are ass-muppets.

Based on the definition given, Bert and Ernie are not ass-muppets. They might be the objects of desire FOR ass-muppets, but unless "Bert and Ernie" is a reference to two flesh-and-blood human beings who like to have sex with muppets, the muppets named Bert and Ernie (not being someones, but pieces of felt with ping-pong ball eyes) could not be ass muppets.