Oh, no! That's wond-, er, terri-, er, horr-, oh, forget the manufactured horror, it's *awesome*! :)
"If you put hair in your Polyjuice Potion, without making sure it's human, you might be a dunderhead!"
I dunno, though. Sev might be more inclined to go around handing out signs. You know: "Say, that's an odd tattoo! Does it have anything to do with that weird skull and snake cloud hanging in the sky?" "No, I used to be a pirate. Here's your sign!" :)