It looks like Robert Pattinson really is all shook up about Riley Keough  but does Kristen Stewart now think he's a hound dog?

The Daily Mail confirms that Rob is in fact dating Riley, who is Elvis Presley's granddaughter, and that Kristen reportedly is not pleased.

Oddly, Rob apparently met Riley years ago through Kristen  as Kristen and Riley were both in the 2010 film The Runaways  but he has gotten better acquainted with Riley over the past few months at Dior events.

Rob represents Dior Homme while Riley was the face of Dior Cherie until recently.

"Riley was always Kristen's friend dating back from their time filming The Runaways, but recently Rob and Riley been spending much more time together since meeting through their Dior modelling connection," says a source. "Riley has stayed over at Rob's Los Feliz apartment." We're sweating while just writing about this hot romance.

However, Kristen is said to be "livid" about Rob's new romance. "Kristen feels that she acted as mentor to Riley on her first film The Runaways, introduced her to Rob, and encouraged her to make a career of acting," says an insider. "Rob has been made aware through friends that she is devastated."

"Kristen is emotionally volatile at [the] best of times and flew off the handle when she found out about Rob's liaison with Riley," adds the source. "She's told Rob via friends she feels violated."

Wow. We can't help but feel badly for Kristen, since Riley is totally breaking "girl code"! That said, it's hard not to acknowledge that Kristen is the one who cheated on Rob last summer. If anyone has had a right to feel "violated," it was him.

So do you think this is a short-lived fling, or will Rob be loving Riley tender for quite some time?

Source: Daily Mail