Seung-Hui Cho hired her to dance for him in a motel room one month before the massacre at Virginia Tech's campus, dancer Chastity Frye said in an on camera interview with a TV station in Roanoke, Va.
"He was so quiet. I really couldn't get much from him. He was so distant. He really didn't like to talk a lot," Frye said in the interview. "It seemed like he wasn't all there."
Frye said that a "creepy" Cho, 23, called the escort service she works for and hired her to meet him for one hour at a Roanoke motel, about a 30-minute drive from Virginia Tech's Blacksburg campus.
About 15 minutes into the performance for Cho, Frye said, it appeared that her client had no interest.
"I danced for a little while and I thought we were done because he got up and went to the restroom and began washing," said Frye, a white woman with blond hair.
Frye told WSLS that she told Cho she was going to leave, to which he responded that he had paid for a full hour and she had only performed 15 minutes.
When she resumed dancing, Frye said that Cho touched her and tried "to get on" her before she pushed him away. Cho then apparently respected her wishes.
Frye said she thought Cho looked familiar when she saw his face in the coverage of the Virginia Tech killings. Cho fatally shot 32 people and then himself on April 16.
She got a call from the FBI, which she said tracked her down through Cho's credit card receipts. Frye said that during a weekend interview, investigators asked her to describe Cho using three words. She chose "dorky," "timid" and a "little pushy."
An FBI spokeswoman from the Richmond, Va., field office, which is overseeing the Virginia Tech case, said the FBI would not comment on possible witnesses.
"I'm not able to comment on who we are and are not talking to," spokeswoman Dee Rybiski told ABC News. "I will confirm that I have had agents there since Monday of last week -- conducting all sorts of interviews."
Mounting evidence of Cho's behavior toward women has emerged in the week since he was identified as the Virginia Tech gunman.
Twice, Virginia Tech police were called in fall 2005 after women complained of Cho's "annoying behavior" on campus.
And one Virginia Tech English professor asked her department head to have Cho removed from class after some female students began to boycott the class, alleging that Cho was taking photographs of them under their desks with a camera phone.
Cho also had an imaginary girlfriend whom he called Jelly, former roommates told CNN. Cho reportedly described her as a supermodel from outer space whose pet name for Cho was Spanky.
On Monday, investigators seized all e-mail account activity records involving Cho and Emily Hilscher, a 19-year-old Virginia Tech student who was among the first two victims killed on the fourth floor of a campus dormitory.
Authorities have not yet confirmed any connection between Cho and Hilscher.