While I don't think it should be required or expected, there is something to say for the anticipation and build up of excitement that comes with some erotic sexting (for many people, at least). If I have an appointment scheduled for 2, 3, or more days in advance, it excites me to know she's thinking about our upcoming rendezvous too. It definitely adds bonus points for her when it comes time for a tip and/or a review. Just my 2 cents worth.