An American Jewish woman has claimed she was hired to be the mistress of Prince Jefri Bolkiah, the playboy brother of the Sultan of Brunei.

Her revelation came just days after Brunei implemented sharia law, which allows residents to be stoned to death for "transgressions" such as homosexuality and adultery.

In her book Some Girls: My Life in a Harem, Jillian Lauren, 36, explained how she was picked to be Jefri's mistress.

Before turning 17, Lauren had dropped out of school to become a stripper. During her career, she was offered $20,000 (£11,785) to perform for a Singaporean businessman.

She soon understood that the man she had to entertain was not a Singaporean, but the Brunei prince.

"[The job] was an invitation to be the personal guest of the notorious playboy prince Jefri Bolkiah, the youngest brother of the Sultan of Brunei," Lauren told the Daily Beast.

"The prince threw lavish parties every night. At these parties there was drinking (which was not legal in public), dancing, some fairly hilarious karaoke, and, most important, women—about 30 or 40 beauties from all over the world, comprising a harem of sorts.

"I spent the next year and some change as his girlfriend."

Sharia law, also known as Islami Qaqun, is the moral code and religious law and is the bedrock of the legal system in several Islamic countries.

Under sharia, sexual intercourse is only allowed between husband and wife. Any form of sex outside wedlock is considered a crime and punishable by death.

Lauren, who has returned to her hometown, suggested that the prince and sultan might not be willing to observe the laws they have implemented.

"It is the privilege of the prince and the sultan to misbehave," she said. "As the citizens of Brunei face the erosion of their rights, I imagine the man I once knew, holed up in a posh hotel suite somewhere, maybe with another American teenager in his lap, making laws that legislate morality."

The introduction of sharia law in Brunei has sparked international outrage.

Many NGOs have repeatedly urged the sultan to withdraw the new rigid penal code, seen as a limitation of freedom and basic human rights.

Many people, including celebrities, are boycotting hotels owned by the oil-rich state's monarch in protest.