It was dark and raining, and the man said he sensed something was not right when he saw the woman that night.
"She looked distraught. She was crying," he said.
"I didn't know what to say to her because she was so upset."
The alleged victim had claimed that she went to sleep in a bedroom after a night drinking, but the man entered the room three times, removing her clothes and violating her.
The court heard on Monday that the woman ran from the house after the third attack and called her flatmate.
The flatmate claimed the woman told her that something had happened to her and she needed to get out.
When the woman arrived home, her female flatmate said: "I gave her a hug, and she just burst out crying."
The flatmate said she had dropped the complainant at the gathering, which was hosted by the defendant, mid afternoon on the day.
Defence lawyer Paul Borich asked the flatmate if she thought the woman, whom she described as "bubbly", could at times be "dramatic" or a "drama queen".
The flatmate said she did not, but that she found the woman to be someone who "never lied".
The woman, who was on Monday accused of concocting the story because she was "prone to dramas" had also insisted she did not make up the attack.
Her alleged attacker is a prominent, professional man, who has been granted name suppression by Judge John Bergseng for the duration of the trial.
The trial continues.