The mother of murdered teenager Ellie Gould has called her killer a danger to women who should never be released from prison.
Ellie, 17, was found stabbed to death at the family's Wiltshire home in May.
Carole Gould said Thomas Griffiths, who has been given a life sentence and told he would serve at least 12-and-a-half years, had become "obsessed" with her daughter.
He stabbed Ellie after she ended their relationship, the court heard during his sentencing.
The murdered teenager's grandmother branded him a "monster" who should face the death penalty.
It was just three months after joining in Ellie's 17th birthday celebrations that Griffiths stabbed her to death at her home in Calne.
The Gould family maintained they had done their best to make Griffiths, who has turned 18 since the killing, feel welcome.
"My husband wasn't overly keen on him (Griffiths) because he didn't say much," said Mrs Gould. "I just assumed it was because he was a 17-year-old boy. It was nothing that would ring alarm bells.
"We welcomed him into our home. We ate dinner with him."
Griffiths even asked to be allowed to do work experience at the family business just days before the murder.
Mrs Gould said Ellie was not looking for a serious relationship but Griffiths was. Shortly before her death, his behaviour changed.
"It was only in the last week that she (Ellie) began to spot some signs," Mrs Gould said. "She said that he'd been acting very strange.
"I said to her 'what are you going to do?' and she said 'don't worry Mum, I'll sort it'.
"Little did we know he was going to turn up the next day and do what he did."
It was a phone call from Mrs Gould's husband Matthew that alerted her to the horrific events of Friday 3 May.
He had come home from work to find Ellie fatally wounded on the kitchen floor.
"I could tell from his voice he was absolutely hysterical," said Mrs Gould. "I was thinking 'what on earth has happened?'
"As I was coming through Calne, a police car was trying to weave through the traffic and I thought to myself 'that's nothing to do with us, is it?'."
It was, and nothing could prepare Ellie's mother for the scene outside the family home in Springfield Drive.
"There were police cars abandoned everywhere, an ambulance at the end of the drive, and Matt just sobbing."
As the stunned couple took in the fact Ellie was dead, officers asked them if their daughter had a boyfriend.
Yes, replied Mrs Gould - but she explained to them how devoted Griffiths was. "He wouldn't harm her," were her words.
But he had.
Within hours, police told Ellie's parents her death was being treated as murder.
"At that point I just felt like I'd been thrown against a wall," said Mrs Gould.
"We both said she didn't have any enemies. Who on earth would want to murder her?"
It was not long before the couple realised Griffiths was the main suspect.
"There was just disbelief that he would do that, and why?"
In August, Griffiths pleaded guilty to Ellie's murder at Bristol Crown Court. Mrs Gould said she wanted him to spend the rest of his life in prison.
"He's a danger to society, particularly to women," she said.
"He became obsessed with Ellie within a matter of weeks. He could become obsessed with another woman and who knows what could happen?"
Ellie's grandmother Pat Gould said Griffiths was "evil" and she believed Ellie's murder was premeditated.
"I believe it should be capital punishment - a life for a life," she said. "Otherwise he's being detained at our expense.
"She (Ellie) had a lovely future and a lovely family to support her and it's been wiped out by this monster."
Ellie's family still feel her loss keenly.
"Her life was full and she had all the opportunities in front of her," said her mother. "She was the perfect daughter.
"When the A-level results came out in the summer, it broke me because I just thought this time next year that would have been Ellie, we would have been talking about her future.
"No mother should hold her dead daughter's hand. That was heartbreaking."