I can tell you this much, by looking at my wife’s browser history. She received a message on facebook entitled “Another way to annoy the boys…”, then she posted “dining room chair works for me”. A little while later a female friend (also a friend of mine) posted “on the stairs, right at the front door (prolly not the best place…)”
So this isn’t the bra color thing, it’s something new, but similar. Maybe something like, “where were you exactly the last time you ate something chocolate?”. I think my wife would rather do that than have sex anyhow. “Where’s your favorite place to masturbate?” would also work, but I don’t think my wife would post an answer to that question.
Too bad the message itself doesn’t get cached, or the whole mystery would be settled.