WARNING: Graphic content

AN Irish architect with a “huge ... urge to rape, stab and kill” women has been given a life sentence for murdering his “sex slave”.

Graham Dwyer, 42, a married, father-of-two architect from Dublin, was convicted last month of luring 36-year-old childcare worker Elaine O’Hara to the mountains in August 2012, where he proceeded to stab her to death before hiding her body.

The case — which has both fascinated and repelled Ireland — included some of the most graphic and horrific evidence ever heard by an Irish jury, The Guardian reported.

During the two-month trial, the court heard that Dwyer’s violent nature and sadomasochistic tendencies were belied by a facade of respectability, with many considering him a good family man whose hobbies included flying model aeroplanes.

Family of Elaine O'Hara pay tribute to her as #GrahamDwyer is jailed for life http://t.co/UoMW8URZz2 pic.twitter.com/E7JUaH1oUs — Her.ie (@Herdotie) April 20, 2015

But what emerged over the course of the trial was a man obsessed with spilling women’s blood during sex acts, whose visits to an alternative sexual underground website to fulfil his deep-seated fantasies eventually led to the death of Ms O’Hara, a deeply troubled and lonely woman who had suffered from mental health issues for years.

Videos showing Dwyer stabbing Ms O’Hara while she was tied up and pleading for him to stop made up much of the evidence against him, as did videos of other women the architect — who depicted them as his “slaves” — had filmed, this time simulating the stabbings.

Investigators are now attempting to find these other women, many of whom were blindfolded at and may not have known they were being filmed.

Ms O’Hara’s body was found by a dog-walker in September 2013, more than a year after she had gone missing. Two days later, police found her bags and mobile phones at a reservoir nearby.

Despite there being no DNA link between Dwyer and the murdered woman, police were able to charge him based on the text messages he had sent Ms O’Hara, which detailed his sadomasochistic sexual fantasies, many of them talking about death.

In one of his most disturbing text messages early on in their relationship, Dwyer wrote to Ms O’Hara: “My urge to rape, stab, kill is huge. You have to help me control or satisfy it.”

In one disturbing message sent to Ms O'Hara after she was hospitalised following a suicide attempt, Dwyer wrote: “You must be punished for trying to kill yourself without me.”

The court also heard of Ms O’Hara’s desperation to have a baby, pleading with Dwyer to make her pregnant.

Dwyer replied: “OK, a life for a life. Help me take one and I will give you one,” referring to another woman he wanted her to help him kill.

Police are also looking into a other unsolved murders which include fatal stabbings.

One case in particular — that of 17-year-old schoolgirl Raonaid Murray, who was killed 14 years ago in Dublin after returning from a night out with friends — has interested detectives.

Since being found guilty, Dwyer has been on suicide watch in prison. His wife and two children no longer visit him, but his parents and brothers attended the trial.

His wife and fellow architect, Gemma, said she was unaware of Dwyer’s activities, but the architect’s former partner, Emer McShea — with whom he has one child — testified against him, saying that Dwyer had told her of his fantasies about stabbing and killing women during sex.

A victim statement from Ms O’Hara’s family said: “[It was] heartbreaking for us to listen to the texts Elaine received from a depraved and diseased mind. The manipulation of her vulnerability was apparent and when she tried to resist, she was reined back in.

“We can hear her voice in those texts, just wanting to be loved. Hearing the contents of the videos will haunt us forever … This is our life sentence. For us, there is no parole.”

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