Katy Perry rocks out in Rio

Katy Perry took the stage in Rio de Janeiro, Brazil, Friday, for Rock in Rio - a Brazilian-based music festival that took place last week.

Throughout the course of her show, the 26-year-old pop star broke out a handful of colorful outfits, including, during her performance of "Last Friday Night," what appears to be a ... long -- and not particularly sexy -- nightgown? (You have to give the girl credit for her seemingly voracious appetite for variety.) 

If Perry's Tweets to be believed, she was pretty excited about the performance ahead of time: "I'M READY TO ROCK RIO! 100,000 people tonight! I LOVE YOU BRAZIL... You've waited so long for me so tonight I'm gonna give it to you!!!" she said via Twitter.

Watch the video of her performance, below, and let us know what you think!