Conan O'Brian -- Swear Word that is not a Swear Word

What was the made-up swear word that Conan O’Brian used to promote on his show? I think it started with a “K”.

You krunkin’ krunker. Go krunk yourself.

How the krunk do you dare bring that word up? Krunk you!

What the krutz is…

No, wait, that’s Nodwick, not Conan. Oh, krunk.