Britney Spears spent Halloween night performing a concert at London's Wembley Arena with Joe Jonas, whom she recently signed on to the European leg of her Femme Fatale Tour. The downside of performing a concert on Halloween, of course, is missing out on all of the trick-or-treating fun. But luckily for Jonas, Spears made up for the candy shortage by performing a little striptease for him, complete with semi-awkward straddling! Here's an incredibly clear and up close video of it. [via YouTube]