Most actresses would rather play the pretty girl than the dorky girl, but not Rumer Willis.

The 21-year-old actress was a back-brace-wearing outcast in the 2008 film "The House Bunny," and plays somewhat of a nerd in her new horror film, "Sorority Row," which comes out today.

"I think it's fun," said Willis, in town last week to promote the movie. "I think as an actor it's important to put your vanity in check. For me, at least, it's too much pressure to have to be that girl.

"It's more fun to play a quirky character. People connect to that more."

Willis described her "Sorority Row" character as "the girl who would finish her term papers for the year" right away, but she insisted she has a sexy side. She gets to fire a shotgun.

"They took me outside 10 minutes before to shoot a couple rounds," Willis said. "It was really fun. I felt really cool."

Few have looked cooler holding a gun than Willis' father, actor Bruce Willis. Did she call her "Die Hard" dad for advice?

"We were shooting at 4 a.m., so I didn't want to call him and wake him up," said Willis, whose mother is actress Demi Moore. "But I did call him later and say, 'You have to see what I just did.' I'm really excited for him to see it."

The film is about a group of sorority girls who covered up the murder of one of their sisters. It's a remake of the 1983 slasher film "The House on Sorority Row," and stars Willis, Briana Evigan, Audrina Patridge of MTV's "The Hills" and former "Real World: San Diego" cast member Jamie Chung.

Although it's a horror movie, Willis said the cast spent most of the time laughing after the director would yell "cut."

She feels the movie has tongue-in-cheek humor, but insisted that it's not a "Scream" clone.

"Ours isn't as campy," Willis said.

" 'Scream' was definitely scary, but ours is really scary. Legitimately. I jumped during the screening — and I know what happens."