"I wasn't able to - in my head - I was trying to get my hands to move or my legs to move, but I was frozen and those messages didn't get there and I was limp", she claimed, fighting back tears.
"I wasn't able to fight him away", she added on the second day of Cosby's trial. In 2005, after the assault and a failed criminal investigation, she filed a civil lawsuit against Cosby and settled. Her claims were supported with testimony by Johnson's mother and her former lawyer, who said they heard about the assault after it happened, and of Cosby's subsequent attempts to have her fired from the talent agency shortly after it occurred.
Constand, a former Temple University employee, said she had viewed Cosby as a mentor.
79-year-old Cosby is charged with three counts of aggravated indecent assault against Constand, which he denies.
They also pointed to phone records showing Ms Constand called Cosby 53 times after the alleged assault.
According to the Cut, Constand reiterated testimony that she previously told police in 2005: Cosby invited her to his residence, where he gave her three pills for stress that he told her were herbal and would help her "relax". He said she testified in 1996 about going to Cosby's home after the alleged assault.
Constand said when she awoke hours later she found her clothes disheveled, her bra undone and as she went to leave the mansion Cosby gave her a muffin and some tea.
Cosby's life and legacy are on the line when his accuser takes the stand in the only criminal case to emerge from the dozens of sexual assault allegations lodged against the actor.
Constand, who was 30 at the time, was at Cosby's Elkins Park home to discuss new professional opportunities.
At this point, Constand claims she "lost consciousness again", waking around 4AM, at which point Cosby offered her "a muffin and tea".
"I trusted him. I wasn't scared of him in any way", said Constand.
A few weeks later, Sewell said, Johnson disclosed that she had woken up next to Cosby in bed with her clothes askew.
She was unable to speak or move to make him stop, she alleged.
Cosby's lawyers have argued that deceased witnesses, lost evidence and fading memories make it almost impossible for them to defend the comedian against the 12-year-old complaint.
Under cross-examination by Cosby's co-counsel Angela Agrusa, Constand was being painted as a gold digger after Cosby's fortunes, a profiteer framing Cosby as fiend not friend. "And so, I just went along with it".
"I did not want to stir up any trouble", she said while on the stand. She says he drugged her - leaving her nearly paralyzed - and then molested her.Cosby, once beloved by American audiences as the dad in the long-running TV hit "The Cosby Show" is not charged in the Johnson incident.