After watching Zac Efron lose his shirt at the recently concluded MTV awards, many women must be day dreaming about dating the "High School Musical" star. However, the good and bad news is that Zac Efron is officially dating "Neighbors" co-star Halston Sag.

A source has recently, confirmed that the blue-eyed actor is actually taken.

"They are definitely an item," a source tells revealed to E!online, adding, "They were seeing each other a bit during filming of their movie together and ever since he went to rehab they got a lot closer. Her friends love him and say he is so sweet. He's really good to her."

The duo was also spotted sitting side-to-side last month at the Los Angeles Lakers at the Staples Center.

Sage was previously dating "Glee" star Chord Overstreet. However, they called it quits according to a source. Prior to dating Overstreet, Sage was also in a romantic liaison with "Big Time Rush" star and "Dancing With the Stars" contestant James Maslow.

Though Sage was not present by Efron's side at the MTV movie awards, he did seem happy and created ripples at the event with his sexy move. Efron kissed a girl from the audience and flashed his ripped body as Rita Ora helped him take his shirt off.

"@RitaOra Thanks for such a bold move. I don't know if I could've done that on my own," Efron tweeted.

Meanwhile, Efron is undergoing drug addiction problem and has been to rehab twice in the last few months. However, reports suggest that he is not still over his addiction and is relapsing. Apparently, good friend Lea Michele is helping him get over the addiction, as she does not want Efron to meet the same fate as her late boyfriend Cory Monteith.

"After he (Cory Monteith) died, Lea became a sober support for Zac. She'd even invite him on hikes through Runyon Canyon. But lately, Zac's been standing her up. She's deeply worried that Zac is teetering on the brink of tragedy, " a source revealed to Hollywoodlife.