In case you haven’t gotten the word; sex between a married husband and wife is supposed to be fun. It’s not just for procreation.
BTW, what do you think Song of Solomon is all about?
Sorry, but once the possibility for procreation is blocked, sex becomes less intense and awesome, less intimate, less joyous, less precious, less real. It no longer explores the deep mystery of persons. It is no longer a real encounter between spouses; it's a fake event because at least one side and maybe both are not all the way in the game. Fun in sex is great, but your reductionist view of the act as essentially fun actually perverts and impoverishes it.