We were stumped trying to decide what Katy Perry was thinking here, so we consulted our Facebook friends.
According to Julie Dawn Sacharko, that look on Katy's face is telling us, "The Muppet had to die."
Thanks, Julie, we suspect many, many Muppets, Fraggles and Smurfs have perished in the making of Katy Perry's costumes. And thanks to everybody else for your comments! Come back next week and give it another shot.