Rihanna had some heads turning backstage at a T.I. concert earlier this month, when she was cozying up to a music man that appeared to be Kanye West!

Sources say the the pop princess and Kanye were reportedly hugged up on a couch -- and then things really got steamy.

"Rihanna and Kanye hung out together after they performed their songs," says a spy.

 

"Rihanna was sitting on Kanye's lap, singing along to the music. Before long, the two were full-on kissing each other."

"People were shocked," the insider continued. "After a while, Rihanna must have realized people were watching, because she had her security escort her back to the dressing room."

That's hot! 

 Other news