Jessica Biel's BoyFriend Enjoying With Mila Kunis: After witnessing the chemistry between Justin Timberlake and Mila Kunis, we couldn’t help but wondering if the Friends With Benefits co-stars were taking their onscreen relationship to the next level in real life. However, on-set insiders tell us that the two are definitely friends WITHOUT benefits! “There is NOTHING romantic going on between Justin and Mila,” one source assures HollywoodLife.com exclusively. “They are just friends. Basically, they go to work and leave – and not together, either.”

Adds a second insider, “Justin and Mila get along like brother and sister. [Rumors that they're together] are laughable.”That’s certainly got to be a relief to Justin’s girlfriend of three years, Jessica Biel, and Mila’s BF of 8 years, Macaulay Culkin. In fact (and perhaps to make sure no hanky panky goes on!) the Home Alone star has been visiting his lady on-set! “Macaulay has actually been [on the Malibu set] alot; he’s very friendly with Justin and vice versa,” reports the second insider.

So who IS JT, 29, spending all of his free time with? Hint – it isn’t Jessica OR Mila! Insiders say that Justin is hanging out with his “Dick in a Box” co-star Andy Samberg! “He spends his time mostly with Andy. They’re together when he has free-time,” our first insider reveals.

When JT isn’t having a bromance with the former SNL star, he IS chilling with Mila, 27, but not in the way you’d think. “When Justin isn’t singing, he’s talking to Mila about Family Guy [where she plays annoying sister Meg Griffin],” the source reports. “He loves that show.”