Piglet's Bathroom Trip

Alright, listen up, you simpleton. You see, Piglet is a character from Winnie the Pooh. And "Poo", that's also a name for poop, okay? This joke is playing on the fact that 'Poo' is part of 'Winnie the Pooh' and 'poo' is what one does in the bathroom. It's a pun, a play on words. You get it now? You're welcome, you absolute buffoon.