The 21-year-old claimed she struggled to breathe and told 23-year-old Ross Smith to stop when they had sex with his hands round her throat.
She told the jury at High Court in Glasgow that after a couple of minutes the strangling stopped but they continued to have sex until she “found enough courage” to get up and leave.
The alleged victim was giving evidence at the trial of Smith, from Cathcart, Glasgow who is accused of raping her after meeting her on a night out while dressed as a nun and she was Dr Frank-n-Furter on October 29, 2012.
He denies strangling her during sex and claims that anything that happened with them was consensual.
The court heard the woman - who cannot be named for legal reasons - went to Smith’s Southside flat after meeting him in Glasgow nightclub Bamboo at a Halloween party, to have sex with him.
She said he stripped off - taking his nun’s outfit off - but accepted she could have helped him take his clothes off and that they had sex.
She said that while on top of her during this, he put his hands round her throat and strangled her.
In her evidence the female told the jury: “I said no. I was trying to bat him away and was gasping for breath.”
Part of a statement she accepted giving to the police was read to the court by advocate depute Shanti Maguire that said: “I was telling him to stop. I couldn’t shout because of how he was strangling me.”
Another part of the statement that said: “I tried to push him off using my arms against his chest but I didn’t have the power” was also read out.
During cross-examination by defence counsel Kevin McCallum she accepted carrying out a sex act on him because she felt she should “reciprocate”.
She also agreed that there was no physical threat or restraint by Smith during any of the sexual activities.
The court heard that she “found enough courage” and left his house without saying anything to him and went to a friend’s where the police were contacted.
It was put to her that afterwards she told someone she hadn’t been raped and she replied: “I know I said it because I didn’t want it to be true.”
She also disagreed with Mr McCallum’s suggestion that Smith strangling her did not happen.
Smith denies the charge and the trial before judge Kenneth Maciver continues.