The Mosuos, a branch of the Naxi nationality with a population of about 15,000, are the main ethnic group scattered in the lakeside villages. The Mosuo people have their own ways and customs, still retain some remnants of the matriarchal society. Men and Women are not bound by marriage, each living at one's mother's home. Men work at home during the day and spend their night with the women they love in their homes. This unique wedlock values affection and gives more freedom to men and women in their relationships. They may choose to unite or separate at will. It has been considered as the living fossil as a basis for a study of social patterns and matriarchal marriage customs in today's world.