Start asking them the same kind of intrusive questions:
- I hear JWs don't believe in oral sex. Is that true?
- Really?!? What kinds of sexual positions are approved? Who decides these things? Has it always been this way? (It hasn't, in case you don't already know this).
- How long have you been married?
- Do you still have sex? I've heard couples that've been married that long never have sex any more. Is that true?