Rigby legally changed his name to "Trash Boat" which caused his own friends to laugh at him. Even worse, he has become the whole town's laughingstock for it.
!! Tropes in this episode include:

* DidntThinkThisThrough: Don't change your name to the first things you see.
* SetRightWhatOnceWentWrong: The Urge went back in time to the present to kill Rigby so that he can stop him from changing his name to "Trash Boat", despite the fact that he had already done it.
* RealityEnsues: Rigby changed his name thinking it would be cool. However the name he chose was stupid, and everybody mocks him accordingly because of it.
* SpaceWhaleAesop: Don't try to change your name, or else you'll steal a famous rock star's fame and his future self will try to kill you because of your new name.