Rape-accused Joseph McCann was branded "pure evil" as a teenager described how at knifepoint.
McCann 34, allegedly tricked his way into a family home in Greater Manchester on May 5.
He tied up a mother with hair straighteners and molested her children, aged 17 and 11, saying: "If you move, I will kill your kids," the Old Bailey heard.
The 17-year-old girl told how she feared becoming McCann's "sex slave" before she jumped out of a first-floor window and
In a video-taped police interview played in court, the teenager described how her attacker had initially grabbed her, put his hand over her mouth and told her to "shut up".
She said: "I managed to wriggle out of it. He pulled me down onto the floor. That's when he must have knocked me out. His knife must have cut me in a few places.
"I was shouting 'mum, mum, mum', but at this point he had the knife.
"My mum was like 'what are you doing?', trying to stop him."
McCann allegedly tied up the mother for being "gobby" and ordered her not to move.
The teenager claims he took cocaine and swigged vodka before repeatedly sexually assaulting her and her brother.
She said: "When I did not do what he said he kept putting the knife up to me.
"In my head I was trying to think of alternative ways of trying to get out of this situation.
"I could not do anything about it. Even in the shower, he took the knife with him everywhere he went.
"He kept brushing it on my skin. That's more like an 'I'm in charge' thing.
She went on: "I mentioned my brother was 11 and he said 'shit I didn't know that, how old are you?' I said 17.
"He said me: 'you are going to Europe tomorrow, you are mine'.
"At this point my life flashed before my eyes. I thought of marriage and everything.
"I'm going to be his sex slave. I thought, I'm not having this."
She added: "We kept being held hostage, being abused at knifepoint. It's scary. It's awful."
The court has heard how the girl fractured her heel when she jumped out of a window naked to escape.
McCann, from Harrow, west London, denies 37 charges relating to 11 women and children.
