July 9, 2012 -- Kourtney Reppert describes herself as a glamour model and an online personality. She posts semi-nude photos of herself online and sends out life-affirming tweets, which has earned her hundreds of thousands of adoring followers.
But in this digital age, where fame can come easy, so can the dark side of such accessible, Internet celebrity: Cyberstalking.
On March 8, Reppert began receiving vile, threatening emails from a man who claimed he would kill her and her parents.
"I'm going to stab you in the f---ing heart and cut your f---ing head off. I will kill your parents, cut them to pieces with a handsaw, do you f---ing understand me? Don't f--- with me or make me mad," one email read.
Reppert, 26, is a small town girl from Pennsylvania who moved to Los Angeles last year to further her modeling career. Reppert said work had been great until she recieved malicious emails from a stalker.
"I will kill you when you least expect it. You are very easy to get to. You know what my demands are. Time is running out," another email read.
Reppert said her stalker demanded that she stop modeling, delete all of her social accounts, move back to Pennsylvania and "be someone else." She was scared for her life.
"He changed the way I view people," she said. "I don't even want to go out. I don't even want to work because I'm so petrified."
Celebrity stalkers have been around as long as there have been celebrities to stalk. In 1980, devoted Beatles fan Mark David Chapman shot John Lennon dead outside of his Manhattan apartment building.
In 1981, Jonathan Norman was jailed after he was caught at Steven Spielberg's L.A. mansion carrying duct tape, a box cutter and hand cuffs. Norman told police at the time he wanted to rape the movie director. That same year, John Hinkley tried to assassinate President Reagan, hoping to impress his real fixation, Jodie Foster.
But the Internet has given rise to cyberstalking, a fast growing problem of public figures being threatened online.
An insurance executive from the Chicago area was sentenced to two and a half years in prison after he pled guilty to interstate stalking former ESPN reporter Erin Andrews. He shot video of her through peep holes in her hotel rooms and posted it online.
And a Canadian truck driver was jailed last year for cyber stalking a teenage actress after he threatened to kidnap her.
"They put the victim on a pedestal, but then once they're rejected, its anger, rage and rejection," said California prosecutor Rhonda Saunders. "The Internet makes it easier with Youtube, with Twitter, because these stalkers believe that the celebrities are actually talking directly to them. They think that they have a relationship, and there's a lot more information out there about the victim."
Saunders, who has handled stalking cases involving major celebrities, including Madonna and Gwyneth Paltrow, said stalkers are seeking "power and control" over their victims and can get sexual pleasure out of scaring them.
"These are people who don't have a lot going on in their lives and all of a sudden, they can pull strings and they can make someone afraid of them," Saunders said. "In their minds, they can see their victims cringing and afraid."
"Unfortunately, we've seen stalkers who not only make threats, but carry those threats out," she added.
Rebecca Schaeffer, a 1980s sitcom star on "My Sister Sam," was stalked for three years by an obsessed fan named Robert Bardo.
Bardo worshipped Schaeffer until the 21-year-old actress did a love scene for the 1989 movie, "Scenes from the Class Struggle in Beverly Hills." After seeing the movie, Bardo went to Schaeffer's apartment and shot her in the chest when she opened the door. She later died at the hospital. Bardo was sentenced to life in prison after confessing to the murder.
Kourtney Reppert's stalker seemed to share that same possessive delusion that she belonged to him and no one else. Reppert said she received nearly 400 vile, threatening messages from her stalker, who knew where she lived, where he parents lived and who her friends were.
"That's what it was all about with the threats," Saunders said. "'How dare she, she's not remaining pure for me, she loves me, and now she's putting these pictures of herself out on the Internet.'"
So why not stop posting photos and tweets, and just delete her online presence? Reppert said doing that would cause her to lose her livelihood and keep her from doing what she loves. The stalker also wins and most likely won't go away.
"It's a Catch 22," she said. "You've got to put yourself out there, but I never signed up for what—this is not something I asked for."
The break in Reppert's stalking case came when she said she noticed a similarity in style between the vile threats and supportive messages posted on Facebook. The FBI first traced the emails to computers in Chicago public libraries, which eventually led them to Luis Plascencia's door, a 47-year-old man who lives with his mother in Chicago.
Plascencia was charged with interstate stalking. He has yet to plead.
"I feel relief, but I don't still feel safe," Reppert said.
The model has now teamed up with former Miss USA Chelsea Cooley to start a website, KourtneyandChelseacare.com, which offers advice and supports other victims of online abuse. But for her, Reppert said the damage is done.
"It's worse right now because all the while the adrenalin these past four months has kind of kept my emotions at bay, and I never wanted this person to see what he's done to me," she said.