A road trip to a cage fighting match turned into a backseat threesome between Wollongong lawyer Katie Foreman, her boyfriend and a female lover involved in her killing, a court has heard.
Ms Foreman died when a blaze engulfed her home in Corrimal in Wollongong's northern suburbs in October 2011.
Wendy Anne Evans has pleaded guilty to her role in the 31-year-old's death.
Bradley Max Rawlinson, Bernard Justin Spicer and Michelle Sharon Proud are on trial for the alleged killing in the NSW Supreme Court.
The Sydney court heard on Friday from Ms Foreman's past boyfriend, Scott Field.
The couple were together but Mr Field knew Ms Foreman had been with Rawlinson, the court heard.
"She said she had broken it off," Mr Field said.
Mr Field confirmed to the court he had been in a relationship in 2008 with Evans, who introduced him to Ms Foreman.
By 2011, Mr Field and Ms Foreman were in a relationship but the court heard Ms Foreman had also been sexually involved with Evans.
The three crossed paths, including when the trio drove to Newcastle to see a cage fight.
On the way home, the three had sex in the back of the car, Mr Field confirmed.
Mr Field recalled one night before Ms Foreman's death, when he had his Harley Davidson motorcycle parked in the solicitor's driveway.
Mr Field saw a white ute behind Ms Foreman's home and confronted a man nearby.
"I had some heated words and he jumped in his car and left," he said.
Ms Foreman later told Mr Field "don't worry about it, let me sort it out".
The trial will continue on Monday.
