Buff Q is basically a joke. It's a video where a person that looks extremely close to Quackity with huge muscles is playing with what it seems like a dog. Quackity confirmed it wasn't him.
Person A: Man, have you seen the Buff Q meme? It's hilarious!
Person B: No? What? Are you okay?
Acronym for Drunken Inner Queen. Used to describe the alter ego many people adopt after getting drunk. Originated within the gay community, but extends to straight people, too.