Niamh Ní Dhomhnaill dated Magnus Meyer Hustveit for almost a year.

They lived together in a flat in Dublin but he would sometimes get angry and Niamh would avoid going home.

Niamh was completely unaware that Hustveit was sexually assaulting and raping her while she slept.

She eventually confronted him and he admitted that he had been abusing her three to four times a week during their relationship.

Warning: This article contains detail some readers may find upsetting.

Niamh waived her right to anonymity to speak to Newsbeat about the sexual abuse, which did not wake her.

"I woke up and my pyjama bottoms were off me," she remembers.

"Then I realised I seemed to be soaked in what seemed to be semen."

He said, 'I've been doing this three to four times a week for the whole time we've known each other'

That was the first time Niamh realised something wasn't quite right. She confronted Magnus and asked him if he'd had sex with her while she was asleep.

"He was totally nonchalant and just said, 'Yeah I did'.

"I said, 'If I'm asleep I'm not able to consent at that point' and he said, 'Fine, I won't do it again.'"

Magnus did it again.

Niamh said what he was doing was strange and asked what had been happening.

"He said, 'I've been doing this three to four times a week for the whole time we've known each other.'"

That was almost 12 months. It was anything from kissing, fondling to penetrative sex.

For help or information on abusive relationships you can visit BBC Advice for links to relevant organisations.

Niamh left Magnus, originally from Norway, and emailed him asking to know more about what had been happening to her.

I'd love to know how he responds to this and what he feels

"I knew there was no point going to the Irish police if I didn't have some form of evidence," she explains.

"I had to be clever about it."

She was hoping he would arrange to meet for tea where she would record a confession from him, but that wasn't necessary.

Magnus admitted everything in an email and Niamh reported him to the police.

It went to court and Magnus pleaded guilty to one count of rape and one count of sexual assault.

He was given a seven-year suspended sentence, meaning he did not go to jail.

The judge said it was "important" to take into consideration Magnus had confessed and without the confession a prosecution would have been impossible.

"There was no expression of remorse throughout the court proceedings and I remember thinking it's strange he hasn't attempted to say sorry," Niamh says.

"It took me so long to find out. I blamed myself in the same way people blame me online. Why am I questioning myself? Why am I putting responsibility for his actions on me? It was something that really tore me up at times.

"I'd love to know how he responds to this and what he feels."

My biggest concern is people will hear this story and then not report rape or sexual assault

Niamh says she remembers hearing the judge say "seven years" but doesn't remember him saying "fully suspended".

It was her mum who had to explain to her Magnus would not go to prison and it's taken four months for that to sink in.

She says she has frustrations with the Irish justice system and she is now appealing.

It's understood Magnus has since returned to Oslo in Norway.

"My biggest concern is people will hear this story and then not report rape or sexual assault," Niamh says.

"For me, I don't think abusers abuse once and it's preventing that from happening."

A view from Rape Crisis

Many people might find it hard to understand how someone could sleep through a rape. Newsbeat spoke to Katie Russell from Rape Crisis, to get her view.

"It's very difficult to say how common it is to be raped in your sleep, largely because sexual assault is something that survivors find very hard to talk about.

"What we do know, is that it is extremely common for someone to be raped, sexually assaulted or sexually abused by somebody they know.

"And very often the perpetrator is somebody who has been trusted or even loved, like a partner, former partner or family member."

"It's very rare for women or girls to lie about sexual assault," says Katie.

For help or information on abusive relationships you can visit BBC Advice for links to relevant organisations.

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