That’s the only joke I know.
I don’t think you’re going to have to try to be funny.
That extra is kissing a horse on the face, and it is beautiful.
Merlin is thinking: “Gosh, it’s good to live in a pseudo-medieval land where humans and horses may openly express their love for each other!”
Arthur is thinking: “HELL’S TEETH, I AM SURROUNDED BY PEASANTS.”