Woman stabbed banker boyfriend to death and left his corpse to decompose for nine days after he flirted with work colleague, court hears

A woman stabbed her banker boyfriend to death at their home after he told her he had 'met someone else' - before leaving his corpse decomposing in their bedroom for up to nine days, a court heard.Joanna Cierpka, 51, tried to cut her throat with an eight-inch kitchen knife when police officers stormed her apartment in Newington Causeway, Elephant and Castle, on March 15.They found the partially-decomposed body of 52-year-old Henrik Slotsaa lying in the bedroom. Investigators found unusual marks on the body which may have been 'an attempt' to dismember his body, they said. 'It was clear he had been dead for some time, as his body showed signs of decomposition, and there was dried, pooled, blood near to him,' said Danny Robinson, KC, prosecuting.Cierpka, originally from Gdynia, Poland, was disarmed and told police: 'I don't want to be helped. You know what happened here? He told me I'm a useless s***. He told me I should kill myself'.She had a deep cut to her elbow and was taken to hospital where she told a member of staff: 'I killed my partner.'Cierpka denies murder, but she has admitted manslaughter.She appeared in the dock via videolink from HMP Bronzefield wearing a black prison-issue jacket. Joanna Cierpka, 51, (left), is accused of stabbing her banker boyfriend Henrik Slotsaa, 52, to death before leaving his body decomposing in their bedroom for up to nine days Cierpka, originally from Poland, denies murder but has admitted manslaughterMr Robinson told jurors Mr Slotsaa, originally from Denmark, worked as a banker at Citibank's London office in Canary Wharf, while Cierpka had worked for British American Tobacco before she was made redundant.He said: 'There is no dispute that Miss Cierpka killed Mr Slotsaa by stabbing him with a kitchen knife.'The issue in this case is whether she is guilty of murder, or whether she bears a lesser degree of responsibility for his death because of her mental state at the time she stabbed him, in which case she is guilty of the lesser offence of manslaughter.'She has already pleaded guilty to manslaughter, but the prosecution do not accept that her plea of guilty to manslaughter adequately reflects her responsibility for his death.'We say she is guilty of the murder of Henrik Slotsaa.'Jurors were told pathologists later found 14 separate 'sharp force injuries' on Mr Slotsaa, with 'slash and stab wounds to the face, neck, arms, and legs'.The prosecutor added: 'There were also unusual wounds to the backs of both knees that may have represented an attempt at dismemberment.'Police officers were carrying out a welfare check on Cierpka when they broke down her front door, the court heard.Mr Robinson said: 'It was only because of the email that Miss Cierpka sent to her family and friends saying she was going to commit suicide that police went round to the flat on 15 March.'The bodyworn footage shows how untidy the flat was, with many empty bottles of wine on the coffee table in the lounge and on the kitchen counters.'Jurors heard friends noted Cierpka had been 'in a bad way' since she was made redundant from her marketing job at British American Tobacco where she had been the 'life and soul of the party'.In the weeks leading to the killing friends say Mr Slotsaa had been 'flirting' with a female work colleague and had told Cierpka on her birthday that 'he had met someone else at work.'Jurors heard Aimee O'Shaughnessy started work at Citibank last September.She met Mr Slotsaa at a work event on November 12 and they 'struck up a friendship,' before meeting for lunch in December, said the prosecutor.Miss O'Shaughnessy disclosed that she was going through a divorce, and they swapped numbers, the court heard.'Throughout January 2026 Mr Slotsaa and Miss O'Shaughnessy met up for lunch on a number of occasions,' said Mr Robinson.'Mr Slotsaa told Miss O'Shaughnessy that things weren't great at home, and he told Miss O'Shaughnessy that he liked her.'She said that her life was a mess and she didn't want to complicate things by starting a relationship with him. According to her, he was fine with this.''They continued to meet up for lunch, and in March Mr Slotsaa said that he was thinking of offering Miss Cierpka £70,000 to move out of the flat they shared.'Mr Slotsaa continued to exchange messages with Miss O'Shaughnessy over the weekend of Friday, March 6 to Sunday, March 8.'Those messages continued until Wednesday, March 11,' said the prosecutor.'It is not known with certainty which of the messages from Mr Slotsaa's phone were sent by him and which were sent by Miss Cierpka, although it is very likely that messages sent after Sunday, March 8 were not sent by Mr Slotsaa, as he was probably dead by then.'In the week leading up to March 13, before police officers found his body, work colleagues became 'increasingly concerned' for Mr Slotsaa's welfare because they could not contact him.'Those concerns started on Monday, March 9, when his line manager, Jane Styles, received a WhatsApp from Mr Slotsaa's phone saying that he wouldn't be into work, as he had woken up with a high temperature.'Miss Styles noticed that Mr Slotsaa had not put his out of office reply on, which she asked him to do, but it remained off.'Other colleagues at Citibank made attempts to call Mr Slotsaa during that week and none of them were successful, the court heard.Police eventually broke into the apartment and found Mr Slotsaa in his underwear, 'kneeling on the floor, with his thighs parallel to the end of the bed.'Mr Robinson told jurors: 'After her arrest Cierpka told a psychiatrist that in December 2025 Mr Slotsaa had told her he didn't love her anymore, and that on her birthday he told her that he had met someone else at work.'Cierpka admitted manslaughter, but denied murder.The trial continues.