The 61-year-old woman was denied freedom, medical help and performed unpaid domestic work, including massaging the man's feet, while sleeping on stairs or in a garage, prosecutors allege.
The victim, who cannot be legally identified, died in 2024. However, her evidence to police, friends and family will be shown to the jury of 14.
Accused slave-keeper Chee Kit "Max" Chong, and his wife Angie Liaw, sat in the back of Victoria's County Court in Melbourne as prosecutors opened their case against the couple on Tuesday.
Chong is charged with intentionally possessing a slave between January and October 2022, and three counts of assault, while Liaw is charged with assisting Chong to keep the woman as a slave.
Both have pleaded not guilty and deny all of the alleged offending.
Prosecutor Shaun Ginsbourg SC said Chong met the woman at church in Malaysia in 2015, and their relationship was like mother and son.
The crown prosecutor alleged Chong tried to get money out of the woman on a number of occasions, including $30,000 just before she moved to Australia with them, which she asked a woman from her church for.
After moving to Australia in 2017, the victim lived with the couple initially, before Mr Ginsbourg said they left to Malaysia without telling her and she became homeless.
The woman allegedly moved back in with the couple in January 2022, to help Liaw with their newborn baby, which is when the prosecutor said the slavery began.
By this point, she had multiple vulnerabilities as she was homeless, on a tourist visa with no independent income and isolated from her family in Malaysia, he said.
"Chong described her to other people as his 'maid or helper'," Mr Ginsbourg said.
"Mr Chong threatened and coerced (the victim) to provide domestic services, repeatedly told her she had to work to repay supposed debts.
"When (the victim) failed at her duties, or failed to complete them to Chong's satisfaction, he would often hit or kick her, or punish her by telling her she could not sleep or eat that day."
Mr Ginsbourg alleged Chong kicked the woman in the head, hit her with a vacuum after she fell asleep while massaging his legs and knocked her head into a wall.
Chong allegedly banned her from eating certain foods and "said she could only eat Weet-Bix", the prosecutor said as he read messages where the woman asked Chong for permission to use the kitchen facilities.
He said the woman was at times forced to sleep on the stairs or inside the garage, instead of a bedroom at their Point Cook home, in Melbourne's southwest.
She was not allowed to leave the home without Chong, including for medical help after his alleged assaults, the jury heard.
Chong's barrister Diana Price said her client never assaulted the woman, denied ever possessing a slave and asked jurors to question why the victim may have exaggerated her claims.
She said Chong denied restricting the woman's freedoms, including her access to food, how and when she slept, and whether she was able to leave the home.
Ms Price asked the jury to look at whether the woman's contribution to the household was different from what you might expect for a family of three adults and two small children.
Mr Ginsbourg accused Liaw of benefiting from the woman's domestic services and asking Chong to give her instructions or tasks, helping Chong in controlling her.
Liaw's barrister Daniel Gurvich KC said she did not commit any crime as there was no evidence she did beyond a reasonable doubt, and the jury's true verdict will be a verdict of not guilty.
