Sven was still a teenager when he realised he was sexually attracted to children.
"There was a case of a 10-year-old girl that had been sexually abused and killed by her uncle," the 26-year-old student says at the beginning of Outing.
"That was when the term paedophilia was on the news.
"That was when I realised that I was like that myself.
"That I was a pig like him who might end up killing someone."
Sven's startling confession opens the documentary that follows his efforts to seek professional help to curb his sexual desires.
Sven does not doubt that his sexuality is repugnant: "And for me that's absolutely clear: any kind of sexual contact with children is taboo."
But looking at a photo album of his youth, he points to a photo of himself, aged 15, with a younger cousin: "I noticed that I felt attracted to her. She was around four."
It is one of many troubling confessions made by Sven throughout the Austrian documentary Outing, which will screen as part of the Antenna Documentary Festival at Dendy Newtown on October 13 at 3pm.
Filmmakers Sebastian Meise and Thomas Reider documented Sven's story for four years after they began researching a project at a German charity that offers therapy for people who are sexually attracted to children but who don't want to act on these desires.
The documentary features extensive footage from Sven's childhood and discusses his troubled teenage years when he felt alone and bullied and contemplated suicide.
Meise said that on a personal level, he and Reider got along well with Sven.
"Of course, you can't judge him for an inclination that developed for unknown reasons in his youth," Meise said.
"Furthermore, Sven is genuinely trying; he wants an outside perspective, so as not to risk euphemising his problems."
At one point in Outing, Sven talks about posting on paedophile internet sites.
Meise admitted it was difficult hearing Sven discuss his fantasies.
"He wasn't telling us momentary thoughts, but recurring thoughts that were haunting him all the time," Meise said.
"He never refused to answer any of our questions; he laid everything open and kept initiating a dialogue."
However, Meise admitted that they found it difficult to trust their subject: "We keep catching ourselves questioning him, analysing what he says.
"That unsettled us; here is a person prepared to expose his inner self, almost obsessively honest, and in return we remain sceptical."
Reider said they attempted to approach Sven in an unbiased way.
He also said Sven was not unusual, with 250,000 people in Germany alone inclined towards paedophilia.
We wanted to find out what his everyday life is like," Reider said. "Sexuality is a big part of all of us; it's impossible to cast off.
"It was difficult at times, because we had to ask intimate questions, but they were important to understand the complexity of the problem."
But Reider said the filmmakers would have ended the documentary if Sven had said he had engaged in criminal acts.
The artistic director of the Antenna Documentary Festival, David Rokach, said Outing was a courageous documentary.
"We wouldn't expect to see such a controversial documentary on TV or commercially screened," he said.
Rokach said the documentary highlighted the lack of options to deal with people like Sven.
"As a consequence the options for Sven are limited; live an unbearable existence or act on his desires and harm other people," he said.
"I think that in this film, Sven is getting the opportunity to create a third option where his desires are expressed."
Outing will screen at the Antenna Documentary Festival at Dendy Newtown on October 13 at 3pm.
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