Today, the jury heard the complainant's DVD interview with police, in which she said there was about two minutes of consensual sex with Sebastian before he began performing acts she did not consent to.
Sebastian had earlier paid $360 for two sex workers, one of whom remained in the room while he had sex with the complainant.
Both women repeatedly told Sebastian he could not do something that had not been agreed upon, but he refused to listen.
"He thought I was his toy and he could do whatever he wanted to. I literally thought this guy tried to control me. He's going to take as much as he gets from me," she said.
"I told him he was hurting me but he continued doing what he wanted to do. The more I said no, the harder and rougher he did it. He thought it was funny."
The complainant said Sebastian prevented her from getting up by putting his arm on her throat.
Both women tried to physically push him away but were unsuccessful, she said.
In her opening address to the jury, Crown prosecutor Nicole Dore said that by law Sebastian did not have the consent of the complainant for the acts that led to the charges against him.
She said the law applied to sex workers in terms of consent as it did to anyone else.
The jury heard that one of the women phoned another person for help, and that person came into the room.
Sebastian had a shower and left. He was arrested as he was getting into a taxi later that evening.
The police were called straight after the incident. Judge John McDonald reminded the jury that prostitution became legal in New Zealand after the Prostitution Reform Act came into law in June 2003.
He said everyone in the country, regardless of their job, religious beliefs, and skin colour, was entitled to the protection of law.
The trial is expected to take three days and continues tomorrow.
