Sabrina and Yasmine Larbi-Cherif shared a flat in Birmingham
A man has told a jury he stabbed his girlfriend and her sister to death at their Birmingham flat because he was falsely accused of rape.
Mohammed Ali, 29, of Old Snow Hill, Birmingham, said he "totally lost it" when Yasmine Larbi-Cherif laughed at him about his time on remand in jail.
He was upset because she accused him of rape and had two abortions against his wishes, Birmingham Crown Court heard.
He admits manslaughter on the grounds of provocation, but denies murder.
The jury has heard that Mr Ali stabbed Yasmine, 22, and 19-year-old Sabrina at their flat in the Jupiter Apartments complex in Birmingham city centre on 14 September, 2008.
Mr Ali told defence barrister Michael Bromley-Martin QC that he met the sisters at a cafe in Moseley, Birmingham, late in 2006.
He said he soon began a relationship with Yasmine who worked as a belly dancer at the cafe.
The court heard he had resumed a sexual relationship with Yasmine after being released from prison.
He had spent five months on remand in prison after being arrested in February 2008 following her rape allegation, the court heard.
The court heard he was charged with 12 offences, but he was cleared of the allegations when the prosecution offered no evidence.
Mr Ali told the jury that on the day of the killings, Yasmine had sex with him at the flat before they discussed his time in jail and her abortions.
"I said, 'remember what you did to me?'," he told the court. "She just blanked it... she was just laughing," he said.
"I just snapped. I couldn't focus on what I was doing - it took over me. I just totally lost it."
Mr Ali told the court he took a knife from the sink in the flat and stabbed Yasmine in the back as she sat on a sofa.
He told the jury he heard Sabrina returning to the flat and felt a blow to the back of his head.
"I remember somebody hitting me," he said. "We started struggling with each other."
The prosecution has told the trial that Sabrina was stabbed 35 times, but Mr Ali said he only remembered stabbing her twice.
He said: "Something just took over my mind and I don't know what it was. I thought I had only stabbed her twice."
The case was adjourned until Friday.