I'm actually telling you to fuck your wife for Christmas and you think there must be some kind of catch. Of course there's a catch. This will become a new yearly ritual for you. You will only be fucking your wife on Christmas from now on. The rest of the year you'll be stroking for me. You're already so focused on being a stroke fiend for me, would you even remember to fuck your wife at all if I didn't tell you to? Perhaps this will be enough to hold your sham of a marriage together.