The father of Becky Watts has spoken of the "despicable act of evil" committed by Nathan Matthews and Shauna Hoare.
In a victim impact statement read to Bristol Crown Court ahead of the sentencing of the pair, Darren Galsworthy spoke of how his world collapsed when he found out his youngest child had died at the hands of her step-brother and his girlfriend in a sexually-motivated kidnap plot.
"I'm the father of Becky Watts now known as Bristol's angel," Mr Galsworthy said in the statement, read to the court by the teenager's uncle Sam Galsworthy.
"We will never understand why this has happened but we now believe we are victims in a plot of hatred and greed.
"This despicable act of evil can never be forgiven or forgotten. When the news came our entire world collapsed.
"I can't describe the searing pain and anguish Anjie and I felt when Becky was found. The only way I can describe it is like being cast off a cliff into despair."
Mr Galsworthy said both Matthews and Hoare callously sat and watched him descend into madness through the worrying about where his daughter was.
He said: "It truly would have been much easier to have taken us all, than have to cope with the aftermath of this crime.
"Everything beautiful in our lives has been ripped apart with one act of violence.
"We can't go outside the house without people pointing at us or making comments they believe we can't hear.
"When I close my eyes to sleep I see Becky's death over and over again. I hear her cry and see her terror, and then her realisation they are not going to stop.
"I feel her heart racing and I am all too powerless to help her. Becky was so small and fragile she never stood a chance."
Matthews appeared in the dock of courtroom two wearing the same grey woollen jumper he wore throughout the trial. Hoare wore a black jacket with a striped blue and white shirt underneath.
Karl Demetrius, 30, and Jaydene Parsons, 23, who admitted assisting Matthews to hide Becky's body parts in their shed, will not be sentenced today.
Demetrius arrived late due to problems with transporting him from prison.
The court heard that Parsons had been excused attendance today for "medical reasons" and would be sentenced at a date to be fixed in February.
Eight female members of the jury returned for the sentencing. The upstairs public gallery was full, as was the downstairs gallery.
Matthews, 28, and his girlfriend Hoare, 21, targeted the 5ft 1in teenager due to their shared dislike of her and an interest in petite teenage girls.
They devised a plan to kidnap Becky from her home in Crown Hill, Bristol, and drove there on February 19 while she was alone.
Detectives say the truth about what happened to Becky that morning may never be known but a pathologist found she died of strangulation.
Becky suffered more than 40 injuries to her body as she bravely fought for her life against porn-obsessed Matthews and his partner.
After her death, the pair dismembered Becky with an GBP80 circular saw in the bathroom of their squalid home in Cotton Mill Lane - less than two miles away.
They callously laughed as they watched a parody of a Disney Frozen song, entitled Do You Want To Hide A Body, while Becky's remains lay just rooms away.
A jury took just three hours and 27 minutes to convict Matthews of Becky's murder while Hoare was found guilty of the teenager's manslaughter.
Both were convicted of kidnap, perverting the course of justice, preventing a lawful burial and possessing two stun gun torches.