Sex with robots seems so obvious that it's not even worth mentioning. Hell they sell torsos that you can have sex with right now, how would making it move a little and look more realistic be any less desirable? If your sex toy can also do the dishes, take the dog for a walk, and clean up the house (ie: you can pretend to guests that it's for something other than sex), why not?
What's more, I can see this fulfilling other roles as well. Obviously the pet thing is priority 1. Want a dog that doesn't crap, and doesn't eat? Get a robot. But what about children? Say you can't have any, or you don't want to go through the trouble of having them or raising them. Why not get a robot child? Guaranteed to stay in whatever stage of life you prefer for as long as you want it to. But problems come when you want to enroll it in school.
Marriage, however, is simply retarded. Marriage is a legal construct for sharing property and children. Can you imagine some dude dying and everything going to his robot? Or someone programs a robot to want a divorce and suddenly we have the robot going to court arguing for half of the money? Or custody of the children? It doesn't even make sense. Perhaps someone no longer wants to take care of their children. Why not marry a robot and give it custody. Problem solved.
