Robert Pattinson Spotted Kissing Mystery Lady

That's just what happend earlier this week when the 27-year-old actor stepped out in Toronto with his Maps to the Stars costar  Mia Wasikowska and her boyfriend, Jesse Eisenberg.

The mystery woman apparently had joined the three for dinner.

But just who is the mystery gal?

Well, a source tells E! News that the person R.Pattz was smooching might be Caitlin Cronenberg, the daughter of director David Cronenberg, who is helming Maps to the Stars.

Of course, the emphasis is on "might" as it is a bit hard to tell for sure.

Either way, the source insists that Rob and Caitlin are just friends.

Meanwhile, rumors have resurfaced that theTwilight star and Elvis Presley's granddaughter, Riley Keugh, have been hooking up.

However, our source again refuted the speculation, saying they are just pals and definitely not dating.