Vanessa Keeps "Her Zac" in Check

Zanessa made sure to keep a three inch radius between them at all times at the Nylon bash the other night

Zac Efron and Vanessa Hudgens may have been totally cuddly cozy at Nylon's Young Hollywood party on Wednesday night, but maybe that's because V keeps her man on a very tight leash.

While at the fete at the Roosevelt Hotel, Hudgens kept Zefron almost a little too close:

"I'm pretty sure she didn't let go of his hand the entire night. Even when they were just sitting down with their friends," dishes an onlooker who was seated next to the couple of the evening.

Maybe that's just because, like, they're totally in love with each other?

Still, 'Ness wasn't exactly pleased if Zac received too much female attention elsewhere.

After the couple posed on the carpet together, they walked in with their group to head to their table outside by the pool. As they were being escorted, Zac (who is a very sociable dude) briefly tapped some girls who were in the way of their route to the table.

"So sorry, excuse us," Zac said flashing those cutey dimples.

Our witness to the not-so-unusual scene tells us the girls looked giddy that the Zefron was there and smiled and chatted with him for a sec until Vanessa (who we think rocked the purple silk dress btw) pushed him forward and gave the brunettes a major staredown.

Totally no biggie, if we could claim Zac's abs, we'd want to keep him in check, too, but we hear from Zanessa insiders her possessive ways are starting to get a tad outta control.

Like how she refers to Efron as "my Zac" in casual conversations. No joke. Jeez, who else's would he be, babe?

It was a little HSM reunion when Ashley Tisdale joined Z and V's girls-only table for a bit. Efron, the lone studmuffin', chatted all of Vanessa's friends up. But always kept one hand on his GF, natch. Gotta keep the cover girl happy!

A few tables away Kristin Cavallari, Brody Jenner, Audrina Patridge, Holly Montag and Stephanie Pratt were all together at the same table. Something we found totally fishy considering none of them actually hang out in "real" life until we saw the cameras filming their every staged move.

Hence the "scream-out" match a tipsy Kristin supposedly got in. Um, hello, don't we all know by now reality shows pick their plot points days in advance?

Vanessa's co-cover girl Ashley Greene was also in attendance, smartly avoiding the rolling Hills cameras and press (given her current sitch) like the plague, but she didn't seem too fazed by the Breaking Dawn drama. She was in a good mood all night, rocking a strapless leopard mini and a black blazer as she hung with gal-pals and one cute mystery man for most of the evening.