Mother-of-two Margaret Henderson-McCarroll, who was just about to go on trial, has admitted the unlawful killing of 67-year-old pensioner Eddie Girvan on January 18 last year.
The 31-year-old heroin addict was to have gone on trial for murdering Mr Girvan in his Station Road home in Greenisland, but instead pleaded guilty to his manslaughter.
Her defence QC John McCrudden had asked trial judge Mr Justice Treacy for Henderson-McCarroll, on her instructions, to be re-arraigned before Belfast Crown Court.
With the guidance of her solicitor, Henderson-McCarroll, her short hair dyed red, and wearing jeans with a blue checked shirt over a white T shirt, pleaded in front of the jury of six women and five men, that she was "not guilty of murder, but guilty to manslaughter on the grounds of diminished responsibility".
Following her guilty plea, Charles MacCreanor QC, for the Crown, said that "the prosecution accept those pleas".
Mr Justice Treacy then remanded her back into custody while pre-sentence and other reports are compiled before sentence next month.
No details surrounding the horrific death were given to the court, however in a bail application last November, the Belfast court heard claims the retired plumber turned amateur antiques collector, was killed in an argument over money for sex.
Following her arrest Henderson-McCarroll, with nearly 100 previous convictions, and with a long-standing history of drug addiction, made several admissions to police.
Belfast Crown Court was also told she claimed that Mr Girvan paid her to have sex with him, that she spent the weekend in his house, and that on the morning he died they had a row over the money.
It also emerged that police found Mr Girvan - his hands and ankles bound together with neckties - with kitchen paper stuffed in his mouth which resulted in his tongue being pushed back and blocking his airway. He had also sustained several stab wounds, including a serious injury to his chest which resulted in internal bleeding.
She told police that during the row, Mr Girvan pushed her and struck out at her with a sword, and that she "poked him in the stomach."
Henderson-McCarroll, also made the case that she gagged him because she didn't want to the neighbours to hear him, and while she denied murdering him, she claimed she acted in self-defence and loss of control.
The bail hearing also heard that she was arrested in south Belfast while on her way to allegedly see a drug dealer, after allegedly selling a gold chain belonging to Mr Girvan for £60 at a Cash Convertors.
In addition to the manslaughter charge, Henderson-McCarroll, living in the Ormeau Centre, in Verner Street, in the Markets area of Belfast, at the time, but whose address on court papers is given as Hydebank Young Offenders' Centre, pleaded guilty to a number of other charges.
They included attempting to steal £20 from the pensioner, stealing his Zodiac watch, a Praktica digital camera, a gold chain, a Garmin SAT NAV, binoculars and a bunch of his keys.
She also pleaded guilty to a series of motoring offences that same day, ranging from taking Mr Girvan's Hyundai Sonata, driving it while unfit through drugs or drink, and with no insurance, crashing it and failing either to stop, remain or report the accident.