Originally I had it as Gamzee and Karkat, but I realised when it comes to jokes, John is simply the best there is.
Wasn't sure if I should post this, but I did - so yeah.
(for those who don't get it: 'Zillyhoo' is the name of John's hammer. He's making a pun. Karkat hates that hammer. Hooray for dumb jokes!)