I would tell THIRD that you don't need to rush into anything with this couple. Asking questions, discussing boundaries and feeling comfortable with the people you sleep with is important. The couple I slept with (and have been invited back to join them when I'm in town again) were super awesome people. They never made me feel pressured to do anything I didn't want to do, and made sure to make me feel included and be considerate both on dates and in the bedroom because they knew I was at a disadvantage. No sex is free from drama, but getting to know people can help minimize that