The Brisbane man who killed and cooked his wife never worked as a chef but used it as a cover story for his real job, it has been claimed.

Close friends of Marcus Volke have said the 28-year-old used the guise to hide his life as a male prostitute, The Courier-Mail reports.

Initially it was thought Volke, who took his own life after killing his wife Mayang Prasetyo and dismembering her body in their Brisbane apartment, worked as a chef after shedding a previous life as a prostitute named Heath XL.

Those close to the couple have now denied Volke was a chef but maintain he met his wife, a transgender woman from Indonesia, while the pair worked on a cruise ship.

Police have appealed for anyone with information about the couple to come forward as the investigation continues into the horrific murder-suicide that has shocked people around the world.

A friend of Ms Prasetyo told the newspaper Volke had bullied and humiliated his wife, prompting a shift in the investigation to focus on whether there was a history of domestic violence between the pair.

"She told me she suffered a lot of mistreatment at his hands, it wasn't just physical fights, it was the mental abuse," Ms Prasetyo's friend of 12 years, Kaisey Bloom, told The Courier-Mail .

"She told me he would get really nasty and would often bring up her past gender disclosure and use it against her."