What do you call someone who is so inappropriate that they are appropriate?

So we have a guy in my office. He can say almost anything. Race jokes, gender jokes, he is just really inappropriate about everything but funny.

He is not a racist or sexist and gets along with everyone fine. He has such a history of being inappropriate that basically anything goes for him. Things that would get someone else a seat in HR, everyday norm for him. He just has no filter. But now his inappropriateness has become appropriate for him.

Edit: I will add that Theodore mentioned "The Office" bosses, both Michael Scott and David Brent. Pretty close I would say. Add in being a little more touchy-feely and not worrying about kissing ass to higher ups and it might be there. The big thing is that people shrug this kind of person off because the person isn't trying to be inappropriate, they just don't know better. So sometimes we get slightly offended, but then we are like... he doesn't know any better. Then we feel sorry for him then people like him more.

Solution 1:

Oaf means someone who is clumsy and foolish, but doesn't say anything about intent or how others perceive the person. A lovable oaf is more specifically what you mean, but of course isn't a single word.

Come to think of it, buffoon is really close, but maybe a bit more insulting than your intent.

Solution 2:

Sounds like an "Equal opportunity offender".

(And yes, the perceived offensiveness may decrease when there's no particular group being singled out)

Solution 3:

A certain politician (in the U.S.) was referred to as the Teflon Man. The outrageous things that he said, that would have hurt almost anyone else's career, seemed not to "stick" to him, but "bounce" off him as if he were teflon.