A 14-year-old girl woke up naked in a bed with two men and does not remember what happened, a court has heard.
The witness, now 16, was giving evidence at the trial of nine men accused of grooming children and exploiting them for sex in Oxford.
She told the Old Bailey she was "off her head" on drugs and alcohol during the incident in December 2011.
The men, from Oxford and Berkshire, deny 51 offences including rape and trafficking from 2004 to 2012.
'Might go mad'
The court heard the incident happened at a guest house in Oxford.
The girl, who is the youngest of six girls who claim they were victims of the accused, has been in various foster placements and children's homes, the jury was told.
When she was 12 or 13 she started hanging around with older Asian men around Cowley Road in Oxford, the court heard.
Giving evidence from behind a screen, she said it was there she met "Tayab", who she later identified to police as defendant Mohammed Hussain.
She told the court he was older than her, in his 20s, and they met "many times" over a few years.
Jurors heard she had sex with him and also with defendant Assad Hussain who she knew as "Ash".
When asked why she had sex with Mohammed Hussain she told the court: "I felt if I didn't he might go mad at me."
The trial is expected to last until May.
The defendants, all in custody, are:
* Kamar Jamil, 27, formerly of Aldrich Road, Oxford
* Akhtar Dogar, 32, of Tawney Street, Oxford; and his brother Anjum Dogar, 30, of Tawney Street, Oxford
* Assad Hussain, 32, of Ashurst Way, Oxford
* Mohammed Karrar, 38, of Kames Close, Oxford; and his brother Bassam Karrar, 33, of Hundred Acres Close, Oxford
* Mohammed Hussain, 24, of Horspath Road, Oxford
* Zeeshan Ahmed, 27, of Palmer Road, Oxford
* Bilal Ahmed, 26, of Suffolk Road, Maidenhead