What the hell did David do to Jessica Biel?

Jessica Biel, on her way to the filming of the Late Show with David Letterman, was wearing grey and looking extremely sexy, but after the show, she appeared exhausted and drawn out. So, I wonder, what exactly went on behind the scenes at the David Letterman show?

At this point, there can only be speculation, but by the looks of it, she may have kicked some unsuspecting person’s ass with her Jessica Biel Manceps

Before the Show:

After the Show: