Swedish doctor who abducted woman drew up a 'sex contract' which would reduce the length of her imprisonment

Martin Trenneborg has gone on trial after he drugged a woman using Rohypnol-laced strawberries and locked her in a soundproof bunker 350 miles from her home

The underground bunker where Trenneborg planned to keep his victim for 10 years (AFP/Swedish police authority)

A Swedish doctor who locked a woman in an underground bunker drew up a “sex contract” which would reduce the time he kept her imprisoned if she obeyed.

Martin Trenneborg, 38, has gone on trial in Stockholm accused of drugging his victim by lacing strawberries with Rohypnol in her home before allegedly raping and abducting her.

She was driven 350 miles to a house close to Kristianstad in southern Sweden where she was locked up in an underground bunker for six days.

He has denied raping her but admitted the other charges.

The contract included a list of sex acts and behaviours which - if she agreed - would give her "discounts" on the amount of time she would have to stay in the bunker, Mail Online reports.

Under the terms, she would be required to give him the "GFE"(or "girlfriend experience") by kissing him during sex and would be required to shave all her body hair, pierce her navel and let him film and photograph her.

The contract - written in English - also said she would be “punished” with additional time in the soundproof bunker if she refused sex, masturbated or tried to escape.

The document - found on Trenneborg’s computer after his arrest in September last year - suggested he was planning to keep her prisoner for ten years.

A courtroom sketch of Trenneborg (left) and his lawyer (AFP)

But Trenneborg’s plan unravelled when he found police at her apartment a week later when he returned to collect some of her belongings.

He forced the woman - believed to be in her 30s - to go to the local police station to call off the search for her but officers became suspicious of her fake story.

The woman told police that Trenneborg - dubbed "Sweden’s Josef Fritzl" - had not raped her again while she was in the bunker but she lived in fear of what he may do.

The entrance to the soundproof bunker (AFP/Swedish police authority)

She said: "Every time he came I didn't know what was going to happen, whether he would rape me or torture me or murder me.

"At one point he told me that if I were to try to escape, he would punish me by chaining me to the bed and I would get nothing to eat but crisp bread.

"He only said that he would keep me there a few years and that he would release me after that."

She also said he planned to bring another woman to the bunker "possibly a celebrity" or the victim’s own mother.

Documents found on Trenneborg’s computer showed he had been planning the kidnap for years and had scouted out at least ten women before settling on his eventual victim.

He said: "She was suppose be my girlfriend for years, that was the purpose. But now that I am imprisoned she will not be my girlfriend in the ordinary sense, even I can understand that.

"She was not suppose to be a punching bag or something. We were suppose to be kissing, hanging out, having sex and stuff that normally people do".

The trial continues.