Girls as young as 11 were forced into prostitution and trafficked around the country by the Oxford paedophile ring.
The gang of seven – convicted at the Old Bailey – used and abused their victims over long periods of time, subjecting them to "extreme depravity", including biting and being horse-whipped.
Opportunities to stop the abuse were missed time and again.
One of the victims described how she was even threatened with arrest for wasting police time when she tried to report the abuse.
The girls were chosen because they had troubled upbringings and therefore fewer people looking out for them.
Between 2004 and last year, they were groomed by the gang – convicted yesterday – who lavished them with gifts or simply showed them the care and attention they craved.
Having secured their confidence, the men would ply them with alcohol and introduce them to drugs such as cannabis, crack and heroin.
The youngsters would become addicted, making them even more dependent on the men, who would also threaten to harm them or their families if they tried to leave.
The girls were often taken to guesthouses or empty private properties in Oxford, some of which were used solely for abuse.
Men would travel from Bradford, Leeds, London and Slough to pay to have sex with the girls in appointments arranged by the gang.
One youngster described two of the men as "the sick sex monsters". Another was branded with a hairpin which was bent and heated up by a man who regarded her as his property.
One girl, referred to as Girl A for legal reasons, felt brave enough to face her abusers in court, while others gave evidence from behind a curtain.
She wept as she described how the gang threatened to burn her younger brother alive unless she had sex with them.
She was repeatedly raped and sold for sex between 2004 and 2007 when she was aged 12 to 15. When she went to police, no action was taken.
"They threatened on a number of occasions to arrest me for wasting police time," she said.
"If you pick up a child who is covered in cigarette burns and bruises, something is fundamentally wrong.
"Adults should be doing their jobs, it's not down to a child."
She said she wanted to see her attackers punished: "I am here to tell my story and see the people who abused me found guilty."
Girl B said she was told she would be shot if she did not have sex with men when she was 14.
Girl D, now aged 19, gave the most harrowing evidence. She was groomed at the age of 11 and turned into a sex slave by an older man.
She had gone to a flat "to chill" and was given drink and drugs. Mohammed Karrar followed her to the bathroom and raped her.
She said: "At the time I thought it was my choice and it was fine, but years on I can see I never had a choice. I said 'no' but I didn't have a say."
He later introduced her to other men and told her to perform sex acts on them. At the age of 12, she was taken to a house in Reading, where she was forced to undergo an illegal abortion on the living room floor.
The gang will be sentenced on June 26.