A western suburbs property manager has appeared in the Perth Magistrates Court charged with demanding money from a married businessman she had slept with.

Peppermint Grove property manager Rachel Roche. Credit:Nine News

Rachel Lorraine Roche, 38, allegedly demanded $150,000 to the man in writing, threatening to tell his wife about the affair if he didn't comply.

The identity of the man, believed to be 50 years old, was suppressed after Magistrate Mark Millington ordered the court to be cleared and refused to hear a submission from Nine News.

In 2014, Ms Roche was embroiled in a Victorian Supreme Court case that saw the contents of letters she had suppressed.