The woman, who cannot be identified for legal reasons, had been in care under the direction of the Court of Protection since she turned 18 in 2013. The court's role is to safeguard adults who do not have the mental capability to look after themselves.
In 2015, a judge ruled the woman could consent to sex but was unable to "make decisions on her contact with men". Carers feared she was at risk of sexual harm if she was allowed unsupervised access to males.
With permission from the court, Manchester City Council employed an organisation, Engage Support, to give her 24-hour support.
A year ago, the woman began making a series of risky attempts to have sex with strangers.
According to The Times, Engage Support threatened to terminate its contract unless the woman was given more freedom.
Court documents say a psychologist employed by the firm believed it would be "in her best interests" to give her "unsupervised contact with men".
The council opposed the plan out of concerns it would expose her to sexual harm, but in June Judge Jonathan Butler gave the go ahead.
Engage Support were allowed to leave the woman alone at home "to have sexual relations with others during daytime hours [10am to 4pm]".
If she asked for sex in public, the documents said, carers would not be expected to physically intervene, but should "remain present". Over the next few weeks she slept with six men.
In August, Engage Support called a halt to the visits, out of concerns about the woman's sexual behaviour and the welfare of its staff.
She is now looked after by a new care provider and the case has gone to the High Court.