A pub landlord died in his prison cell before police could question him about the death of a carer who also worked as a cam-girl.
Jerome Dangar was under investigation for manslaughter after Hope Barden died of asphyxiation.
The online sex-worker had been taking part in a bondage session at her home in Staffordshire when she died, Stoke Sentinel reported.
Dangar, who had paid the 21-year-old to take part in the risky activity, did not call for help despite being able to see she was in distress.
The 45-year-old died in his prison cell at Dartmoor Jail in April 2019 having been locked up for possession of extreme pornography.
As well as auto-erotic strangulation, Dangar had ab interest in snuff videos which showed people dying, an inquest jury in Exeter, Devon was told.
Dangar stockpiled prescription medication propranolol, a drug used to treat anxiety, in his cell before he was found dead, a Home Office pathologist said.
The jury at Exeter's Coroner Court heard Dangar had been on remand at HMP Exeter before he was jailed in January 2019 at Truro Crown Court for 15 months.
He had admitted nine charges of possessing extreme pornography of acts that portrayed threatening a person's life and endangering their genitals.
Judge Simon Carr said the 47 images and videos included 'the deliberate torture of people who are clearly alive at the beginning and seem to be dead at the end'.
He told Dangar, who ran a pub in Tintagel, Cornwall, 'these offences are in my view the worst of their kind'.
The judge said a pathologist reviewed the videos and believed 'at least three of the people being tortured were dead by the end'.
Prosecutor Philip Lee said the images showed a 'pre-occupation with strangulation, stabbing, torture, asphyxiation and death'.
The senior Devon coroner Philip Spinney told the jury that Dangar was transferred to Dartmoor a few days after he was jailed at Truro Crown Court.
A day before he was found dead, he learned he was to be re-interviewed by Staffordshire Police about the manslaughter of Hope, who was found dead at her home in Burton-upon-Trent on March 15, 2018.
The coroner said Dangar was prescribed medication for anxiety and was allowed to keep the pills in his cell.
Dangar wrote letters talking about suicide but told his parents he 'did not have the bottle to hang himself'.
Dr Deborah Cook, the Home Office pathologist, said Dangar had an extremely high level of Propranolol in his blood and urine.
He also had Sertraline in his system but she said this did not cause his death and was not in a fatal range.
At Hope's inquest, a conclusion of unlawful killing was recorded.
A coroner there heard that Dangar was a depraved 'snuff movie' fan who left her to die after watching her suffocate on a live sex webcam.
It was said she was paid to perform 'degrading and dangerous' acts by Dangar after he met her on an adult website where she was earning money to top up her wages as a carer.
Dangar paid £2,300 over three months to watch her and police later found abuse videos at his home.
The Exeter inquest jury recorded a suicide conclusion on Dangar after an eight-day long inquest at Exeter Coroner's Court.
Following Hope's inquest, her mum Katie issued a statement through Staffordshire Police.
She said: "Hope was a beautiful, intelligent young woman. She had completed her foundation degree in adolescent mental health and had recently returned from working in Norway.
"Hope had paid work in the Burton area as a carer for people with learning disabilities. Hope had been earning extra money working in the online adult film industry.
"Unregulated, this industry serves no-one except those who wish to perpetrate violence against women.
"Hope became the subject of interest of a regular user of the site who paid her to perform sexual acts via the internet, which over three months of contact escalated into degrading and dangerous situations.
"We are sorely disappointed that this case can no longer bring any legal justice for Hope. Had this gone to court, this would be a landmark case, the first of its kind in the UK.
"As it is, we will be issuing our report and findings to every police force in the UK in the trust that should a dreadful situation like this arise again, there is a record of how we approached such a sensitive and difficult issue.
"Anyone with daughters or other relatives involved in this terrible industry must be aware of the risk of harm.
"A duty of care exists in any relationship. If someone is obviously in danger, one has a legal obligation to take steps to help.
"In this tragic case, Hope was left to die. Hope's family and friends have been devastated."
