Zac Efron might not be dating "Neighbors" costar Halston Sage for too long as sources are claiming that the 26-year-old has a "wandering eye."

According to Hollywood Life, after insiders confirmed that the movie couple was "definitely an item" a new report claimed that his on stage kiss with a woman from the audience at the MTV Movie Awards was just a glimpse of what the heartthrob is capable of.

A pal close to the "That Awkward Moment" star revealed, "The girl he kissed at the MTV Movie Awards on stage was on his mind afterwards as well.

"He kept flirting with her after the segment, even holding her hand on the way to the back and rubbing her back."

Meanwhile, his fellow stage presenter and costar Dave Fanco, gave his lucky lady from the audience a quick peck and kept his hands to himself afterwards. He is currently dating "Mad Men" and "Community" star Allison Brie, 31.

A source told the celebrity gossip site that while dating Zac Efron, Halston Sage, "better keep her eye on him if she wants it to work because his actions would make any other girl very leery about pursuing a relationship further."

Earlier this week an insider revealed that the pair has been dating for a short time. The pal told Us Weekly, "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 new couple was spotted earlier this month sitting courtside as the happily cheered on the Los Angeles Lakers at the Staples Center.

Less than a week after photos of Efron and the blonde at the basketball game surfaced, news broke that Sage and "Glee" season 5 star Chord Overstreet split.

Before hooking up with the hot "That Awkward Moment" star and dating Overstreet, Halston Sage was romantically linked to "Big Time Rush" star and "Dancing with the Stars" contestant James Maslow.

 Meanwhile Efron has dated the likes of Vanessa Hudgens and Lily Collins.