Girls just want to have fun!
Kelly Rowland and Demi Lovato are doing just that while on the road with The X Factor!
Their latest stop was Denver, Colorado. That's when the two co-judges decided to pull a prank on Simon Cowell!
They served him up a local delicacy called Rocky Mountain oysters - otherwise known as BULL TESTICLES!
Simon then spit the bull balls out as soon as he realized Kelly and Demi were messing with him. When they told him what he had just eaten, Cowell chugged mouthwash until the taste was gone!
But Simon still wanted to have a little fun of his own!
He then offered up the gross grub to Paulina Rubio!
Poor Paulina! We hope she didn't fall for it!
Ch-ch-check out a shot of the tasty testicles below!
[Image via Dennis Van Tine/Future Image/WENN.]
Tags: demi lovato, funny, gross, kelly rowland, paulina rubio, prank, simon cowell, the x factor, tv news