The Woman of Yen-chou is a figure from Chinese/Buddhist folklore who is often associated with Kuan-yin. She lived in eastern Shensi during the Tali era (766-779). She slept with any man who asked her. Having sex with this woman was a special experience because after having sex with her a man was said to become completly free from sexual desire. She was considered a woman of ill repute and after her death buried without ceremony in a common grave. Some time later, much to the mystification of the villagers a foreign monk came to the villiage to offer incense and pay respect to her at her grave. The villagers asked him why he would bother with a husbandless woman of loose virtue. He told them that she acted out of compassion. When she slept with all those men she did not to satishfy her own needs, but in order to cure them of their desire and help them towards spiritual transformation. The monk predicts that if her bones would be found chained together, (a sign of a holy person or bodhisattva) and when they dug up her grave they were.

Sources: Chun-fang Yu. "Kuan-yin: The Chinese Transformation of Avalokitesvara"