The title of this article is conjectural. Though the topic is found within The Simpsons universe, a proper name is not available.
The "Ha ha!" couch gag is the twelfth couch gag of Season 9.
The Simpsons go to sit on the couch but fall on their posteriors when the couch gets pulled back. Nelson Muntz comes from behind the couch and exclaims his catchphrase "Ha ha!", as the family looks back at him with annoyed expressions.