Is Ryan Phillippe moving on from Amanda Seyfried to Rihanna? Phillippe is rumored to have had a hot and steamy night with Rihanna earlier this month, and though the original reports were that she blew him off at a Gucci/Roc Nation event in NYC, it appears to have been quite the opposite.

Per Us:

“She thinks he’s hot,” says the source. “They totally had sex. And it wasn’t even the first time!

According to the source, the initial hook-up happened back in December when things weren’t really working out between Rihanna and Matt Kemp. Since then the couple have done their best to keep things discreet and out of the public eye as much as possible. However, it seems that their plan failed. Since then, the two are said to have been regularly, but quietly, seeing each other. This comes following a surprise birthday party Saturday arranged by Kemp, who has been linked with Rihanna since last year.

“There was no PDA,” says an attendee of the Los Angeles party. The next day, he went to her 23rd birthday party at a Beverly Hills home. Says an onlooker, “They hung out a bit, but were discreet. It is still very casual.” Sums up another source, “Clearly they’re keeping it on the downlow!”

Seyfried has adamantly denied a break up with Phillippe, saying “That Rihanna story is not true. That is so f**king not true!” Phillippe, for his part, has denied the Rihanna dating rumors, angrily declaring they are “not true” when asked. Who HASN’T Rihanna been linked to?

Click here to see who is pregnant and sporting a bikini!

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Images Via: WENN