Graham Coutts admitted ten years before murdering Jane Longhurst: "I want to rape and strangle a woman."

Yesterday a jury of five women and seven men at Lewes Crown Court unanimously found him guilty of a murder that had fulfilled his chilling ambition.

Coutts, 35, a part-time musician, faces at least 30 years in prison after being convicted of strangling special needs teacher Jane, 31, with a pair of tights on March 14 last year.

He had denied killing the talented viola player, of Shaftesbury Road, Brighton, claiming her death happened when a consensual sex session went wrong.

Jailing Coutts for life, Judge Richard Brown said: "Everything that this court has heard about Jane showed her to be the sort of person who enriched all those who came into contact with her.

"The undoubted love of her partner, her life, her work and her music and her family screamed out of every page of the evidence I have heard in this case. In seeking perverted sexual gratification by way of your sordid and evil fantasies you have taken her life and devastated the lives of all those she loved and who loved her.

"By persisting in your denial you have put them through the ordeal of this courtroom and have forced them to live the last moments of her life and by the unbelievable degradation of her body you have shown not one jot of remorse."

Jane's boyfriend Malcolm Sentance shouted "bastard" at Coutts as he was sent down to the cells.

Coutts' former partner, Sandra Gates, leant towards him over the dock and shouted in his face: "You pervert."

Jane's sister Sue Barnett and her mother Liz Longhurst wept openly in the public gallery.

Detective Chief Inspector Steve Dennis, who was in charge of the case, said outside court: "A very dangerous man has been put away and I'm very pleased for that."

Coutts kept Jane's body in storage for 35 days, at first in a flat above the home he shared with his pregnant girlfriend in Waterloo Street, Hove, and later at the Big Yellow storage warehouse in Brighton.

He visited the body on several occasions. Detectives who searched the store following his arrest found a used condom.

On April 19, Coutts took the naked body to Wiggonholt Common near Pulborough and set it on fire.

Coutts was known to have a dark side.

Former girlfriend Sandra Gates said he once told her: "I want to rape and strangle a woman."

Another ex-lover told how she caught him hiding in a wardrobe watching her young daughter undress.

The woman was so worried she persuaded him to seek professional help.

Coutts saw a psychiatrist with the old Brighton Health Authority in the early Nineties but after an initial consultation he refused treatment and failed to show up for appointments.

He enjoyed his fetishes too much and no one could force him to have therapy.

As one police officer in the case said: "If they locked up everyone who came to them needing treatment then the prisons would be overflowing."

There seemed little anyone could do.

Dr Michael Rosenberg, consultant psychiatrist and chief executive of South Downs Health NHS Trust, which provides mental health services, said: "People have to be motivated to co-operate with the services that might be able to help them with a variety of problems.

"This kind of tragedy is very unusual. Many people have fantasies which they do not act upon."

Coutts had made a half-hearted attempt to exorcise his demon but it came back with a vengeance on the morning Jane Longhurst rang to speak to his partner.

The night before, Coutts had been downloading pictures of dead women, strangulation, rape and murder as he had done for eight years.

Jane's call presented him with an opportunity to fulfil his perverted ambitions - and she was the perfect victim.

Jane was pretty and nice. Police wondered if it was her look of innocence, her unblemished character, that so attracted the devil in Coutts.

Jane had a vitally important physical feature that attracted him - a long neck.

Coutts, 35, had had a fetish for squeezing women's necks since he was 15 and he indulged in strangulation sex with girlfriends.

Two women agreed to strangulation sex to satisfy his lust.

Sandra Gates, 11 years older than Coutts and his on-off girlfriend for seven years, found pornographic photographs taken by Coutts of a previous girlfriend Nicola Stainthorpe.

He had drawn a noose round her neck on the pictures.

Coutts told Ms Stainthorpe about his fetish a month into their relationship and while she thought it "a bit odd" she allowed him to perform sexual asphyxiation 100 times during their two-year relationship.

After splitting with Ms Stainthorpe he began seeing Lisa Stephens, moving into her £170,000 ground-floor flat in Waterloo Street in the autumn of 1998. She was soon introduced to his fetish.

There were other women. When Coutts and Ms Stephens split for a few months in early 1999 he moved out and rented a room in Portslade.

He met a girl called Nina in Southampton and indulged in bondage and "breath control play".

He moved back in with Ms Stephens but they split again in summer 2000, this time for a year. He rented in St Aubyns, Hove, and had a one-night stand with Norma Blundell.

She let Coutts tie her up with gaffer tape, the type musicians use to stick cables to the floor.

He regularly viewed some of the most vile web sites imaginable and downloaded thousands of pictures involving murder, rape, strangulation and even necrophilia.

Police, revolted by a crime they had never before encountered, have no direct evidence he committed necrophilia but have strong suspicions.

He visited the body in the Big Yellow storage unit in Coombe Road 11 times, sometimes only for a few minutes.

He said he couldn't bring himself to dump it. Jane was a friend and the discovery could shock his partner so much she might lose the twins she was carrying.

Police are convinced his motives were more sinister.

Mr Dennis, in charge of the case, said: "It is possible Jane was sexually assaulted in the Big Yellow.

"There was a used condom and its package in the box."

The condom's torn wrapper was also inside the unit. If he had used it in his flat, why had he not disposed of it earlier?

It was the ultimate manifestation of his obsessions.

Coutts spent hours in his room with his computer downloading images and mini films. Records show he was active on the internet on evenings immediately before and after killing Jane.

He had even burnt a CD to store the images.

Not surprisingly, people found Coutts strange and creepy.

To them, him strangling, possibly raping and having sex with Jane after she was dead was shocking but not entirely surprising.

Many were reluctant to talk but one woman said: "There was always something dark about Graham."

Some close to him couldn't or wouldn't believe it.

Even Jane's partner Malcolm Sentance was disbelieving at first and reportedly passed on good wishes to Coutts after his arrest.

Mr Sentance had no idea he had been so wickedly betrayed by a friend; no idea Coutts would try besmirching Jane's reputation and character by suggesting she had been unfaithful by agreeing to a kinky sex session with him; no idea he would drag Mr Sentance's professional and private life through the courts, all to save his own skin.

Coutts' 37-year-old partner probably believed his story that Jane's death was an accident during consensual sex.

She has not spoken publicly but has stood by him. Like most, she must wonder where it all went wrong.

The couple had been trying for a baby for two years and turned to fertility treatment after Ms Stephens miscarried in 2001.

She gave birth on October 11 last year, six months after Coutts murdered Jane. She had been eight weeks' pregnant when Coutts used a pair of her tights to strangle Jane.

Ms Stephens, an English teacher at Cardinal Newman School in Upper Drive, Hove, is believed to be living with her mother in the city and her flat has been rented out.

Neighbours had no idea who they were living next to. One said: "He always smiled and said hello. He seemed quite a nice chap."

Miss Stephens has said very little other than to close friends. Protecting and nurturing her children are now her only priorities.

One of her friends said: "She is quite a strong, matter-of-fact person. Her world has been turned inside out but she is someone who gets on with life."

Ms Stephens has visited Coutts in Belmarsh high security prison, south-east London, where he has been on suicide watch. Once she took their twins.

One day, she will have to tell her sons about their father.