Are you serious? It's "Mister" in mexican.
Well context would be everything, wouldn’t it?
People seldom use “mister” in a sentence construct the way you did and I had no idea Fierro was Mexican. So you throw in one Spanish word in a sentence about someone whom I have no idea of his nationality and I am supposed to clairvoyantly ascertain that it is Spanish. Apparently he’s not as legendary as you thought.