She was in mid 30's and was married to a man in late 40's who had a daughter (from his first marriage) in her late teens. They were hosting an exchange student from Africa, age early 20's. I don't remember how they started, but the wife first started having sex with him and then the daughter followed! No threesomes, the man was fucking them seperately. The father/husband learned about it, accepted it and he was keen on watching his wife. The young man stayed for over a year at their home, he had to go back to his country because his VISA had expired but they were thinking of ways how to bring him back.
The interesting part is that the daughter had a boyfriend but both women thought the black man was the best lover they had and they were fucking him daily! She told me he was long lasting and very good on getting hard again quickly!
I forgot to mention they were in Western Europe.