The first complainant to testify at the trial of Edmonton bar promoter Matthew McKnight told court on Thursday she was sexually assaulted during an event at a bar on Whyte Avenue.

The woman said she was 18 years old the night she and a friend attended a glow-paint party at Lucky 13 in November 2011.

Many of the men at the party were bare chested, while women sported bikini tops so they could have their bodies decorated with paint that glows under black light, the woman testified in Edmonton Court of Queen's Bench.

McKnight, dressed in a dark suit and taking notes in the courtroom on his laptop, pleaded not guilty last week to multiple charges for alleged sexual assaults dating from 2010 to 2016. Under cross-examination, his defence lawyer suggested McKnight and the woman engaged in consensual sex.

The complainant recounted the night on Nov. 10 at a party at Lucky 13, where she ran into McKnight. She said they had met at another bar a week earlier where she and her friends joined a pub crawl he had organized.

She said McKnight gave her free drinks, and later, when she was "extremely drunk" led her down the hall to the liquor storage room. He poured another shot into her mouth, before taking her to the manager's office, she said.

She said they may have kissed. He then took her hand and put it down his shorts and she stroked his penis. The woman testified that the next thing she remembers was that her pants were down and he was penetrating her anally, without consent.

"I was just in shock that that was the position I was in, and it was just so painful it was hard to collect my thoughts," the woman said.

She said the anal intercourse lasted a few minutes before she finally found her voice and told McKnight to stop.

She said he stopped and they put their pants on. But before he unlocked the door he asked that she not tell anyone, and she agreed.

Later that evening, the woman said, McKnight approached her on the dance floor to confirm that she wouldn't tell anyone what had happened.

She said she bled from her anus for the next four days and was sore for at least a week but didn't seek medical attention because she was too embarrassed.

McKnight faces 13 charges of sexual assault. His jury trial started last week and is expected to last another 10 weeks.

After McKnight was initially charged in August 2016 more than a dozen additional complainants came forward, including the woman who testified on Thursday.

She brushed away tears as she recalled hearing about McKnight's initial charges in the news, then hearing it had prompted more women to come forward.

In October 2016, the woman reported her experience with McKnight to Edmonton police.

"I felt responsible that he had been able to hurt them," she said in court.

Under cross-examination, the woman agreed that she knew McKnight was sexually interested in her when they met at The Rack a week earlier. But she insisted her interest was only in the free drinks he offered and not sexual. The woman agreed the pair texted over the next few days and danced closely together at Lucky 13.

She acknowledged she could not remember any of the conversation that had taken place before the sexual contact or what happened just before intercourse.

"You have a complete blank in your memory about how that happened?," asked defence lawyer Bottos, to which the woman responded "correct." "And if you have that blank you also can't tell us who was responsible for pulling down your pants."

Bottos put forth an alternate version of events, which the woman repeatedly objected to.

He said she touched McKnight's stomach, complimented him on his physique and leaned over to kiss him. McKnight said "sorry not here" but assured her he wanted "to do naughty things" to her, Bottos said. When McKnight offered to take her to the office, she responded positively, the lawyer said.

Bottos suggested both of them had a shot in the liquor cage where four people were playing a drinking game, before walking hand-in-hand to the manager's office. Botto said McKnight touched the woman with her approval, that she pulled down her own pants and when McKnight took a condom out of his wallet and told her to turn around, she did.

"And with a condom on he penetrated you vaginally, not anally, isn't that right?," Bottos said.

"No," the woman responded.

The woman conceded that there was no independent medical verification that McKnight had penetrated her anally. Bottos questioned how she could return to the dance floor afterwards, if she was in pain. He suggested that McKnight had asked her not to tell anyone because he was not supposed to be having sex in the office with a patron.

"You don't want to admit that you engaged voluntarily in consensual sexual intercourse with Mr. McKnight," Bottos charged.

"No that's not what happened," the woman responded.

Between 2011 and 2016, Bottos said McKnight and the woman continued to text. She agreed when they ran into each other she acted like nothing had happened because "it was easier." She said she might have accepted his invitations to the club, but couldn't remember.

The woman is the first of about a dozen complainants scheduled to testify. The next woman takes the stand Tuesday.