Justin and Mila are definitely Friends With Benefits... and we've got the proof

There hasn’t been an ‘are they or aren’t they?’ this big since Brad Pitt got together with Angelina Jolie .

But after Now saw Mila Kunis and Justin Timberlake, 30, at London’s Dorchester hotel last week, we’d put money on the fact that they definitely ‘are.’

We watched the pair giggling, sneaking around and enjoying a private meal, but the highlight came when Mila, who turns 28 this week, serenaded Justin.

Mila was in high spirits all night,’ says our source.

‘She 
was in the bar first, looking for him.

‘The pianist was playing Elvis Presley‘s All Shook Up and Mila joined in, singing: “I’m in love, I’m all shook up,” as Justin walked in.’

Read the full story about Justin Timberlake and Mila Kunis in Now magazine dated 15 August 2011 – out now!

Now cover 15 August 2011

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