Musuo

There were no lifetime monogamous marriages but women could choose a different man or no man or the same man each night

Instead of the father taking care of their children the women's brother would help take care of the women's children

In exchange that women's brother would not have to take care of his own children

Supposedly crime, violence & STDs were low before the Chinese government intervened & forced marriage

They did not have the same "fatherless" behavioral problems as blacks