We're not surprised to see some underb00b pics pop up on Rihanna's Instagram. Is it for Chris Brown?<br /><br />For more Hollywood news and gossip:<br />http://www.youtube.com/hollywoodbackstage<br /><br />Subscribe at: <br />http://www.youtube.com/subscription_center?add_user=HollywoodBackstage<br /><br />Like us on Facebook:<br />http://www.facebook.com/hollywoodbackstage<br /><br />Follow us on Twitter:<br />https://twitter.com/#!/HollywoodBstage
