Benjamin Michael Jomaa took the innocuous social media photos of the women and used technology to turn them into explicit faked images.
The 32-year-old manipulated a photo of two sisters holidaying in Thailand to make it appear as though they were topless before sending it to them both on Facebook, according to the agreed facts of his NSW court case.
He sent matching graphic messages to each sister before threatening to post the photos online if they didn't respond with real explicit images.
"Respond or you will regret it," the sales assistant wrote, as outlined in court documents.
He used a very similar method to sextort a mother and daughter, whose photos he scraped from their Facebook profiles and photoshopped to appear as though they were topless.
Sexual extortion or "sextortion" is a form of blackmail where a person threatens to share a nude or sexual image or video unless their victim gives in to their demands.
Another woman received a number of very graphic descriptions of Jomaa's fantasies about her along with a demand to perform a sex act for him.
He was motivated to extort intimate images out of the victims for his own sexual gratification, police say.
The 32-year-old has admitted targeting eight women over seven months, leaving them deeply concerned the deepfake photos would be published online.
According to the agreed facts, the edited photos appear real and would not arouse suspicion.
Jomaa faced Gosford District Court on Thursday after pleading guilty to 17 offences, including eight counts of using a carriage service to send sexual material knowing the recipient did not consent.
He was expected to face sentencing but the matter was adjourned to allow the magistrate to read all of the relevant information.
The Ettalong Beach resident will instead learn his fate in April.
After previously defying attempts to photograph him, he ducked his head and attempted to obscure his identity as he entered and exited the courthouse.
When Jomaa was arrested in May, police found all of the photos - both edited and original - in a hidden folder on his phone.
He was charged two months before the NSW government introduced a bill to specifically ban AI-generated sexual imagery.
Under the laws, editing a photo to create an intimate image of someone while being reckless as to their consent carries a maximum penalty of three years' imprisonment.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
10°C