This is the person who you would meet in Prison, inevitably, if you ever were to screw McDonalds (the Fast Foods-restaurant chain) badly enough to get your self locked-up for your prosecutable crime against Them.
(F.Y.I., Mayor McShiv is most deadly when he teams with his own Partner In Crime, **The Ass|Burglar.**
if you see these two together ... well, you had better run away, as fast as you can, ´less you want to wind up a Bloody, Cummy, Holey, Traumatized Mess.)
actually, "Mayor McShiv" was introduced to The World, for the first time, as a part of the punch|line of one of Conan o'Brien's hilarious Monologue Jokes, on a May 11, 2006 taping of 'Late Night with Conan o'Brien'; whereäs with The Ass|Burglar, it would appear as if _he_ has been around, for millennia -- suffice It to say, The Ass|Burglar definitely is _not_ exclusive to the McDonalds' brand.
anyway, "McShiv" is a play on the word "McCheese," as in 'Mayor McCheese,' who himself was an actual part of The McDonalds' "Family," up until some point-of-time in the 1970s; if you'd like to get some background on this **Mayor McCheese** fella, you get It from Wikipedia.
The Actual Joke in which The World was Introduced to **Mayor McShiv**:
Conan o'Brien -- "This week, true story, a man in Chicago was sent to prison for five years for embezzeling $600,000 from McDonalds. Friends say while in prison he should watch out for Mayor McShiv and the Ass Burglar."
Conan o'Brien's Audience -- "(gasps in horror at the thought of Gay Prison Sex)"