Mosuo people is belong to Naxi, their culture is so different as others, they are still keep the Matriarchal society, and they don't have the Marriage system, Man do not need to marry a woman, woman don't marry to a man. When man and woman meet on a event or an anniversary, they like each other, the man will go to this woman`s house from the window at midnight, and the man have to leave before girl`s parent wake up, and when he leave he can take the door, but if he meet the parents when he leave, they will think it`s kinda rude.  This is a traditional way of Mosuo people how to breed, and after the woman gave birth to the baby, the father will admit he is the baby`s father and will treat all the family when the baby one month old.
This is so different as nowadays, but i think the relationship between them are much easier than in the modern city, and maybe not many people can accept this culture at all.
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