In the micro-budget movie "Luvrgrl," she's anything but.

That's because she plays an NYU coed named Zoe Ferrara, who goes from young and innocent to campus slut in the wink of an eye.

She gives a brave performance in a tough role, but she almost didn't get it.

She twice auditioned for the part. First time, she was rejected because director Lee Bennett Sobel thought she looked too old.

"Being a 21-year-old actress being told she couldn't play an 18-year-old was quite a blow to the old self-esteem," dark-haired Benisch confessed over brunch at French Roast in the West Village.

Second time, she never heard back, and another actress got the job.

"But a week before they started shooting, the girl dropped out. So I got a phone call with an offer."

That left the actress a week to rehearse what she called a "very intense and traumatic role," one which required her to have sex with a woman and several men and to bare her body quite often.

Were those scenes difficult?

"I wouldn't say they themselves were difficult. I choose to do this because I thought the story was important.

"The thing that was difficult is that we did most of the explicit scenes in one day, and it was the first day of shooting. It kind of felt like a gang bang."

Director Sobel had nothing but kind words for Benisch:

"It was not easy for her to go through all the stages of Zoe's sexual addiction," he gushed in an e-mail message. "I think she is going to be a major talent."

"Luvrgrl" is Benisch's first starring role.

She has done off-off-Broadway theater and some student films. Plus bit parts in the movie "A Beautiful Mind" and two episodes of TV's "Sex and the City."

And starting March 6, she'll be in "Henry IV" at the York Shakespeare Company in New York.

Of "A Beautiful Mind," she reported:

"I wouldn't say I worked on it, I wouldn't say I was in it, because all you see is my silhouette in the background. But I was there and I saw Ron Howard and Russell Crowe doing their thing."

She said "Sex and the City" was "a fun set to work on. I learned a lot."

What do her parents, who live in a tiny Pennsylvania hamlet, think of "Luvrgrl"?

"I was honest with them about the content," Benisch - who was wearing jeans and a demure pink sweater - said.

"My dad said he'd like to see it, but to tell him when the sex scenes were coming so he could get up and get popcorn."

Video-shot "Luvrgrl" will screen at 7:30 p.m. Saturday and next Sunday at Freight, a restaurant-nightclub at 410 W. 16th St.; (212) 242-6555. Try www.lofientertainment.com for a DVD copy.

V.A. Musetto is film editor of The Post. He can be e-mailed at vam@nypost.com