The Auckland District Court heard on Wednesday that the man told his students that intimate touching was essential to their education.

A woman who alleges a famous actor sexually assaulted her says the man encouraged her to kiss his penis during an acting class.

She detailed how they embarked on a brief affair after they developed feelings for one another, after his alleged offending against her.

The woman sobbed in court as she described being "pushed" to respond to his kisses and touches, after he offered her secret one-on-one acting classes at her modelling agency.

The man, who can't be identified, has denied 10 charges of indecent assault and two of sexual violation against four complainants- his acting students.

READ MORE: Actor on trial at Auckland District Court

At the opening of the Auckland District Court trial on Wednesday, jurors were told by the Crown that the man told the complainants they needed to be sexually uninhibited to be better actors.

Lawyers for the actor say the women made the claims up because they felt "slighted" when he ended a relationship with the first complainant.

The first complainant to give evidence on Wednesday cried as she described how the acting exercises allegedly progressed from kissing and touching, to oral sex.

She said he would make her feel guilty if she didn't comply.

Giving evidence from behind a screen, the woman said the man was a "figure of inspiration" to her and although she felt she wasn't a good actor, he always encouraged her.

She said he first used a push/pull exercise to kiss her on the cheek, and then on the mouth, which she said "startled" her and made her nervous.

On one occasion he allegedly pulled his pants down and showed her his penis, encouraging her to touch it and kiss it, which she initially declined, she said.

Eventually she complied, but by that stage she said the pair had a close relationship and she trusted him, she said.

She told the court their relationship changed and he often spoke about his marriage to her and told her his problems.

"He became almost a father figure... The trust kept growing. That's why I did it (kissed his penis), because he asked," she said.

'IT'S HARD FOR ME TOO'

The woman, then aged 21, said she was told she was part of a select group of people to whom the man offered private acting sessions.

The one-on-one classes were in a small room with the windows blacked out and the man would always lock the door, she said.

She gave evidence that the man took off her pants and performed oral sex on her during one of the tutorials.

She pushed him away and burst into tears and he responded by giving her a hug, she said.

"He said, 'I know it's hard but it's hard for me too ... I'm scared too. I'm really proud of you. I know that was really hard for you but I was with you the whole way, and I'm glad you took the jump.'"

He knew that she was uncomfortable, but was conscious of wasting his time, she said.

He constantly spoke of "missed opportunities" and she felt bad if she didn't respond to his advances, she said.

"If there was someone going out of his comfort zone for me, I felt like I had to respond. He was saying, 'I'm here doing this for you, how can you open these boxes and overcome your inhibitions?'

"I just believed he was helping me. I looked up to him ... What I really wanted to do was progress and that's what he was telling me I needed to do to progress."

Eventually the kissing became more forceful, and he would grab her by the neck, she said.

The first time she felt it had gone too far was when he allegedly grabbed her by the breasts.

She responded by saying no and pulling her arms around herself to protect herself, and he finished the session, she said.

"By that stage I could see that, gosh I really am being pushed."

'EMOTIONALLY AND PSYCHOLOGICALLY MANIPULATED'

Later the pair embarked on an affair.

"I started to have feelings for him, unfortunately," she told the court.

"I believed that he was someone who genuinely cared for me and had my best interests and knew all about me and was helping me progress and was there when I was down.

"He was also helping me progress not just in acting...but as a person."

She believed her romantic feelings for him were reciprocated and on his return from a trip overseas he bought her gifts.

Not long after that they had consensual sex in a hotel room for the first and only time, she said.

Sometime later she heard other women had made complaints about the man and was directly asked if she had experienced something similar.

At first she denied it but later "suddenly everything became clear," she said.

"I realised what had been happening and I felt I had just been emotionally and psychologically manipulated and I didn't know what was real and what wasn't. Everything was a blur. I had no idea what was right or wrong anymore.

"Was I actually a good actor? Was I actually developing the last year, 18 months? Does he actually like me?"

She told the modelling agency what had happened and said she was told they were aware of it and other girls had been affected.

However it wasn't until a year later, when the man continued to teach, that she got in touch with the other complainants and they decided to lay a complaint with police, she alleged.

"I heard he was still teaching which didn't sit with me."

'INTIMATE TOUCHING WOULD MAKE THEM BETTER ACTORS'

In her opening address Crown prosecutor Claire Paterson said the case would be about informed consent.

"In this trial the Crown is going to be inviting you to carefully consider the issue of consent. What does it mean to genuinely consent to sexual activity in the context of acting tutorials?"

After each exercise where the defendant allegedly touched the four complainants, he told them they were making great progress but that they were sexually inhibited, Paterson told jurors.

"The defendant suggested that engaging in exercise that involved intimate touching would make them better actors," Paterson said.

She said the actor offended against the alleged victims in a "methodical way" which gradually escalated in its seriousness and lead the complainants to believe it was a necessary progression in their acting education, Paterson said.

"The complainants were uncomfortable with this but believed as their teacher the defendant had their best interests at heart. In short, they trusted him."

In a short opening address the man's lawyer, Ron Mansfield, said the evidence would be "hotly contested".

Although the two exercises involved kissing and embracing, the man denied he ever touched the women on their breasts or genitalia, Mansfield said.

The complaints had their genesis after the man's affair with one of the complainants ended, following his reaffirmation of his commitment to his wife, jurors were told.

The man was "not proud" of the affair and was disappointed in himself, Mansfield said.

"You will hear that all four complainants got together at various different points, with the encouragement of other people, to lodge these complaints and to exaggerate them to the point where it involves the touching of the breasts and genitalia," Mansfield said.

The trial is expected to take at least two weeks.