Probly just an add-on. The Cougar S for one has different taillights, for two as far as I know (which isn't a lot, so somebody correct me) there was only one Cougar S actually made, and it was sold at a Ford Auction where they auctioned off many of their concept vehicles, and for three, all the pictures of the Cougar S that I've personally seen have it as a Champeign type color, not what looks to me as Laser Red.
So I think it's just an "S" badge. Like when you can go to the dealership and get the "COUGAR" letters they are seperate...maybe he just bought, or found an "S" somewhere and slapped it on there?
But this is just my input...what is the link where you found this?