The four complainants conspired after he ended an extra-marital affair with one of them, his lawyer says.
This afternoon, one of the women told the court their secret one-on-one sessions became increasingly sexual as he touched her breasts over her clothes and asked her to touch his crotch.
He told her the contact was to advance her as an actor and that it was helping her, she said.
It escalated to a point when he pushed her down in a chair, unbuttoned his trousers and showed her his penis, she said.
"He said, 'Come on, just a little kiss. Come on', in a light-hearted way. It wasn't angrily."
The woman, who was in her early 20s at the time, said this continued to happen in the context of a "Push/Pull" exercise where they would react to each others' actions.
At this point the one-on-one sessions happened twice a week and cost $30 a session.
"Eventually I complied. I just closed my eyes and leant forward and did a peck."
She said the coach then pulled up his pants looking pleased then sat down in his chair "grinning".
Crown prosecutor Claire Paterson asked why she complied.
"The same reason as all the other acts - [he] had become someone that I trusted and I genuinely believed he was trying to help me and had my best interests at heart. And i felt close to him as well."
The sexual contact during their sessions stopped for a few weeks but when it returned, the relationship had changed and they'd become romantically involved, the woman said.
They would meet to kiss and chat about both their lives, including the problems in his marriage, and when he returned from a trip to the States he bought her a T-shirt and chocolates.
He asked to meet him at a motel - she agreed and they slept together for the first and only time, she said.
Shortly afterwards, in July 2013, the affair ended.
At a dinner with friends, it was raised that other girls had experiences similar interactions with the acting coach.
"Suddenly everything became clear, what had been happening. I realised that I'd been emotionally, psychologically manipulated ... I had no idea what was right or wrong anymore," she told the court.
"I realised the whole thing was false and wrong."
The woman was put in touch with management who told her it was "being handled" by the agency but a year later when she heard he was still teaching, she contacted the other women.
They decided to go to the police with what happened.
In his brief opening statement this morning, the coach's lawyer, Ron Mansfield, said the evidence would be "hotly contested" and his client denied touching the women's breasts and genitalia.
He said the complaints had been exaggerated because the women felt slighted.
The woman will be cross-examined tomorrow and the trial is expected to take two weeks.
