When the woman turned toward him, McFadden said, the man grabbed her, pulled her into an alleyway, and sexually and physically assaulted her.
The man also took $150 in cash from the woman's back pocket, McFadden said.
The man fled and the woman returned to the bar around 11:45, McFadden said, where she told a friend what had happened and the two left for a hospital.
The woman described her attacker as a black man with a muscular build, standing between 5 feet 8 inches and 5 feet 9 inches tall. He was clean-shaven with shoulder-length braided hair. The woman described him as well-dressed, with a blue button-down shirt, khaki pants with a brown belt, and a silver chain with a cross on it. She told police he had a small tattoo on his neck.
McFadden said police believe the incident occurred on the 1200 block of St. James Street and have been canvassing the area since Thursday for witnesses. They're also looking to review security camera footage from the area.
Tabu's owner, Jeff Sotland, on Wednesday said he was still trying to determine whether the woman had been a patron there. His block of 12th Street is under heavy video surveillance, he said, and at least four video cameras are trained on St. James Street.
McFadden said the woman is "doing as well as can be expected" after the attack, and suffered bruises and abrasions during the assault.
"There hasn't been a sexual assault of this nature in the area in quite some time," he said.
Police, he said, are "always concerned" about assailants striking again.
"It was an aggressive, blatant attack on a victim," he said. "Of course we're always staying vigilant out there."
Anyone with information on the incident may call the Special Victims Unit at 215-685-3251.