A man left his 83-year-old mother "moulded" to an armchair for two years before she died at their shared home, a court has heard.
Hazel Kimber was found dead at a house in Seaview, Isle of Wight, in 2015.
Anthony Kimber, denies manslaughter by gross negligence and causing or allowing the death of a vulnerable adult at Winchester Crown Court.
Prosecutors told the 61-year-old's trial that he failed to obtain medical help for his mother.
Jurors heard paramedics found the "severely malnourished" pensioner's body in the house in Ryde Road after Mr Kimber, her full-time carer, dialled the NHS 111 non-emergency number.
Sally Howes QC, prosecuting, said Mrs Kimber had not been in contact with health workers for five years before she died on 31 August.
"The chair appeared to have moulded to her shape and was rotting away under her," she said.
"Her spine was rigid and concave by the position in which she had been sitting for so long."
'Smell of urine'
Mr Kimber told police his mother had been in the chair for two years, the court heard.
Parts of the house were in "utter squalor", with a "strong smell of human urine, excrement, mould and general decay", Ms Howes told the jury.
She added: "Anthony Kimber had known his mother was unwell for a noticeable time yet failed to obtain any medical assistance or advice."
She said the defendant told police he was carrying out his mother's wishes not to contact a doctor.
"If Mrs Kimber had had to go into a home, Lexden [their shared home] would undoubtedly have had to be sold to fund this," she said.
The prosecutor said the defendant's "lack of action" had caused his mother's death, which was from a combination of the effects of malnutrition and blood clots in her lungs.
William Mousley QC, defending, said Mr Kimber's mother was "frightened" of doctors and did not want to leave her home of 75 years.
"At the forefront of Anthony Kimber's mind was his duty to respect the wishes of his mother," the barrister said.
Mr Mousley added the pair had chosen a "reclusive" life that might seem "eccentric... even disturbing to some".
"Quite simply their existence was really not much more than that, and not what many people would describe as a life," he said.
In a statement read out in court the paramedic who found Mrs Kimber's body said the house was "like the Addams family, spooky".
She said Mrs Kimber's chair had "completely disintegrated" and the hallway was "thick with dust and cobwebs to the point that it was black and soot-like".
The trial continues.