Season 6, Episode 20: "The Doodle"

But after a while...

...no matter how much willpower a person may have...

...it won't matter...

...because they're crawling, crawling on your skin.

Up your legs, up your spine, up your back--

All right, I've got them! I'm rife with fleas!

Oh, that feels good.

Hey, this guy charges 100 bucks an hour...