If you’ve ever read the ingredients label on pop princess Katy Perry you will notice she contains 100% of the recommended daily allowance of fun in every serving! Her latest serving is in the form of a photo she tweeted yesterday featuring herself in some sexy form-fitting South Park pajamas and a bottle of Dom Perignon champagne! (Click image to enlarge.)

Katy’s caption for the image is. “celebrating all the love from the #1′s around the world in my new South Park pj’s on the bus! (whilst being photo bombed)”

The pajama set was created by fashion designer Jean-Charles de Castelbajac for his chain of JC/DC stores and Katy sent out props via her Twitter account after posting the photo, tweeting “@jcdecastelbajac check out my last photo post! Wearing your south park top & stretch pants that were @ Colette! Yay, thank God for JCDC!”

Castelbajac is a favorite designer for many of pop culture’s funnest fashionistas including Lady Gaga, who wore Castelbajac’s now-infamous Kermit the Frog muppet-inspired coat for an interview last year. Katy also got in on the Castelbajac muppet love last October when she was spotted out in Paris wearing a fun JC/DC muppet dress.

I tried to find a runway or retail image of Perry’s PJs without any luck. If anyone out there has a link to where folks can get their own pair of JC/DC South Park pajamas, leave a comment! Also, if you know who that is doing the photobombing in the background let us know! (Is that Castelbajac?)