Sexuality between robots
Each function in human life gets support from feelings which protect the ground for that function, protect it's health. So a human like robot could have humanb like feelings. But since it is different from humans, it cannot form very close instinctual bonds with humans, it cannot form a family with humans and it cannot learn talents and skills from humans - but it could from a robot, so some kind of sexuality between robots would be possible. For it to affect positively, it should be healthily analogious to human sexuality:
If a robot has a certain view to the world, it would be best suited to a life that that view supports best. But if it lacks skills, if it's basic structure in what comes to ways of doing, i.e. if it's habits are of a wrong kind for that kind of life, then it needs to settle for something less. Unless it would learn from another robot that has habits and skills well suited for that kind of life. It could admire those skills, take them as it's goals, copy them from the more skilled robots, it could adjust it's ways to suit that kind of robots' wyas of living and doing, so changing to that type of robot itself. That would be something like sexual bonding.
So a humanoid robot could be a little bit like humans in this sense too.
(IN a complex society with robots it would be easier to handle things well if each robot would be self-correcting this way too, kind of building itself toward better functioning in it's free time. So each part could itself find roughly the right kind of place for itself, and so everything would not need to be as programmed from up above as traffic lights are.)