A reclusive family refused to believe their sister was dead after she stopped eating, and embalmed her body at their cottage, an inquest has heard.
Rina Yasutake, 49, shared a home with her mother and siblings in the village of Helmsley, North Yorkshire.
Suspicions were raised at the local chemist in September 2018, when her brother Takahiro, 51, and sister Yoshika, 56, repeatedly bought bottles of surgical spirit over a period of days.
Staff at the pharmacy reported that they smelled of "corpses", North Yorkshire Coroner's Court heard today.
Emergency services were called to the property and paramedics found Rina's dead body under a duvet on a mattress on the floor, on September 25, 2018.
While it was obvious that she had been dead for weeks, the family continued to believe she was alive, the inquest was told.
It was later established she had been unresponsive since August 18, though the date of death could not be conclusively determined, the inquest heard.
She was in an advanced state of decomposition to the point of mummification and a postmortem could not ascertain a cause of death.
Craig Hassall KC, representing the family, asked Detective Inspector Nichola Holden, who led the police investigation, if the family was "utterly convinced" that she was alive when the emergency services attended.
The detective replied: "They were at the time and for many months after."
Home Office pathologist Dr Jennifer Bolton said it was hard to determine how long Ms Yasutake had been dead, given the extent of mummification, but that the level to which it had developed took "some weeks".
The brother, sister, and their mother Michiko Yasutake, 80, were charged with preventing a lawful and decent burial, but the prosecution was halted when it was found the family members suffered from a rare mental disorder.
Coroner Jon Heath was told there was no evidence of any third-party involvement in her death, no sign of injury or toxicological cause.
Rina Yasutake, who was Japanese, was a talented pupil and won a scholarship to Cambridge University where she studied classics, specialising in linguistics.
She did not work after university and the family had lived together in Helmsley for 20 years, the inquest was told.
In statements given to a psychiatrist, the brother and sister said that during the course of 2018, Rina Yasutake stopped eating, became weaker, and began to move less and less.
Earlier that year, it was recorded that Ms Yasutake, who was 4ft 11in tall, weighed just six stone, six pounds.
Yoshika Yasutake told the psychiatrist: "She didn't say much so we said to her to eat and drink more.
"She looked like she was being nourished by eating her soul.
"I don't know how to explain. Even though she was not eating, she was nourished with spiritual food and she was fulfilled."
The family said Rina had been behaving strangely after their father's death, but had not sought any medical treatment since 2013, when she was given counselling after seeing her GP about an "aggressive episode".
Mr Hassall described his clients as "a very insular and isolated family" and Ms Holden agreed that even when using a Japanese interpreter, communication was difficult, as they spoke their own dialect.
The family were self-reliant and isolated, living first in Nunnington after their mother married a British man and they left Japan.
Ms Holden said that during the course of inquiries, it was found they had no means of communicating with the outside world and no TV or radio.
Mr Heath recorded an open conclusion, saying: "I am unable from the evidence available to determine how she died."
The family, who still live in the same cottage, did not attend the inquest but Mr Heath said they will listen to a recording of it later.
