There had to be a reason that Justin Timberlake would let a hot babe like Jessica Biel get away—and the reason is Mila Kunis! Justin and Mila got hot and heavy onscreen while shooting the new film “Friends with Benefits” last year, and now that Mila has dumped longtime BF Macaulay Culkin, the starry pair is ready to go public.

So far, both are keeping it quiet. A source told E!, “Justin is very interested in Mila. They’ve been flirting, but so far nothing has happened.” Another source told People that Mila had nothing to do with the breakup of Justin and Jessica. “There really wasn’t a final straw. They’re just two people who realized they wanted different things in life and were headed in different directions.”

Did anyone really expect Justin and Jessica to live happily ever after? The “Sexy Back” singer has dated a bevy of famous beauties, starting with Britney Spears when both were teens, and including Cameron Diaz. Justin shows no signs of settling down anytime soon, and Mila better be aware of this if she lets their flirtation get serious. Still, she’s very hot right now, thanks to “Black Swan,” and being half of a celebrity couple would only amp up her star power.