There was a sorority at my mom's high school in So Cal. They were called the Denotians and you could only join if you were invited to... my mom was invited, but declined because she didn't want to be limited to one group of friends (they didnt talk to anyone outside of the Denotians)... She said they did silly things for the girls getting initiated (wearing pins, wearing clothes inside-out to school, getting them drunk), but that was about it. I'm not sure if it was designed to filter into the NPC system, but the majority of my mom's friends that were in it did end up going greek (I think a lot were USC Pi Phis)... that's about all I know
