NORRISTOWN, Pa. — Defense attorneys for Bill Cosby on Wednesday sought to discredit the testimony of his sexual assault accuser Andrea Constand, a day after her dramatic courtroom confrontation with the entertainer.

Launching their cross-examination of the former Temple University basketball coach — the prosecution’s most important witness — the defense suggested that the 2004 encounter at Cosby’s home that is the subject of Cosby’s sexual assault trial was part of a two-way romantic entanglement, not an attempt to prey on an unwitting victim.

But prosecutors and the accuser’s mother, Gianna Constand, rebuffed those attempts and insisted that Constand’s relationship with the entertainer was based on nothing more than work and friendship.

The elder Constand in particular jolted the courtroom, especially when she discussed a conversation in which Cosby conceded that “it sounds like I’m a perverted person.”

The entertainer’s lawyer, Angela Agrusa, peppered Andrea Constand with questions about an earlier night when Constand was on the bed at Cosby’s hotel room at Foxwoods Resort Casino in Connecticut, as well as an earlier dinner at Cosby’s home that involved alcohol and a lit fireplace.

The approach led to a somewhat bizarre courtroom sequence in which Agrusa tried to play up the romantic qualities of Cosby and Constand’s earlier encounters while Constand played them down.

“Your bodies were touching, and you laid there for at least 15 minutes,” Agrusa said of the night at Foxwoods, where Cosby had invited Constand to see him perform.

“No, I was reclining with my elbow, with my feet off the bed,” Constand replied.

And did he open the door while wearing a robe? the defense asked. “He was in a white shirt and pants,” Constand said, slightly annoyed.

Constand has accused Cosby of giving her pills and violating her sexually while she was unconscious at his home, the basis of three charges of indecent aggravated assault.

Agrusa also recounted the details of the first dinner at his home some time before the night Constand alleges he attacked her.

“So you knew on that first night that you were alone in his home, sitting by a fire and drinking brandy, that Mr. Cosby was interested in you in a romantic way,” Agrusa said.

“No, ma’am, he never said a word to me,” Constand replied.

Agrusa later said, “He was coming on to you. He was buying you presents. He was showing affection.” After a pause, Constand replied, “Yes.”

Prosecutors replied to the defense’s claim of Constand’s interest by characterizing her as simply a polite and pragmatic employee of Temple University, where she worked and Cosby was a trustee.

The argument was made even more strongly by Gianna Constand, taking the stand late in the day.

“Andrea never shared anything with you” about their romantic relationship? Agrusa asked in her cross-examination.

“No. Because there wasn’t anything to share,” Gianna Constand replied.

More feisty and defiant than her daughter, the elder Constand recounted a phone conversation in which she pressed Cosby on the alleged sexual assault.

“I said, ‘Tell me everything you physically did to her.’ He said that he was touching her breasts. He said, ‘Mom’ — he called me Mom throughout the conversation — ‘Don’t worry, there was no penile penetration, just digital penetration,’ ” she said.

“He was talking about it almost like he was leading me to believe it was consensual, or it was OK. He was manipulating it,” she said. “He said to me, ‘Mom, she even had an orgasm,’ ” she added. “And I was fuming.”

Gianna Constand said she “got very aggressive” and asked about the unidentified pills Cosby allegedly supplied her daughter. Cosby said he would mail her the name of the prescription, she testified, but never did.

“I kept asking, ‘Why did you do that to my daughter?’ I said, ‘My daughter was sick. Why didn’t you call 911?’ ”

Cosby responded, Gianna Constand said, that “ ‘I feel bad telling you about it. I feel like it sounds like I’m a perverted person.’ ”

He offered to pay for the younger Constand’s therapy. She declined and said she just wanted an apology.

“And he said, ‘I apologize to Andrea and I apologize to you, Mom,’ ” she recounted.

Demonstrating Constand’s awareness of Cosby’s romantic interest would have little bearing on whether she gave consent during the interaction in question. But legal experts say the knowledge could color the jury’s perception of the night — if they got it right.

“It was essential that they make the [romance] argument, but I’m not sure the way they presented it that it resonated with the jury,” said Dennis McAndrews, a former Philadelphia-area prosecutor who has been in the courtroom observing the trial.

In addition to the buildup to the January 2004 night, Agrusa also sought to show that Constand maintained interest in Cosby after the incident, laying out phone records that showed some of the 53 calls the defense says she made to Cosby.

“So in the month and days after the alleged assault, you were calling him with a lot of frequency, weren’t you?” Agrusa said.

The lawyer focused on about half a dozen calls of varying duration to Cosby’s home in New York over a particular 24-hour period.

“You called him on Valentine’s Day,” Agrusa said.

“I called him on the 14th,” she said.

A number of the calls she made, the prosecution showed, came after she had checked her voice mail, presumably responding to a message from him rather than initiating contact. There were no calls, the prosecution and Constand noted, for more than four months after she left her job and moved back to her native Ontario.

“Once you left Temple, was there any reason to speak to this man?” said the prosecutor, Kristen Feden.

“No,” said Constand.

steven.zeitchik@latimes.com