I think most of our real close friends have an idea that there si a certain amount of d/s going on. I've never been open to be shy about sex when talking to my good friends, most of them enjoy sex as much as i do. exploring trying new ideas etc... I've been spanked bitting growled at reprimanded in front of several of them, and i assume they either took it for what it was or as playfulness.
My family hasn't seen us for any long period of time, so I really don't think they have ever witnessed any thing too suspicious. But I think they would probably just keep quiet... however we might have scared his younger sister on occasions as she used ot hang out wiht us and our friends alot...
ON a side note...
polygamy is marrying multiple people... i think unless she considers herself wed to both of them you meant polyamory, which is loving more than one person. Sorry, living in utah the definition of polygamy is always in the news and I have a few friends online who are in polyamorous relationships...