First of all, thank you for taking the time to incorperate the apostrophe, so you deserve the correct definition. Makin' love (or making love) is a term absorbed my modern "culture" used to justify the forinication between 2+ people. This is equipt with a power that which makes sex sound less repulsive, girls feel less insecure about being a hussy and guys feel like they are chivalrous (yet, they rarely use it and when they do, its hypocrisy and they need to be shot in the mouth.) The word is a contribution to modern society's centralization around sex.
A man can say that he fucked a woman or he can say he made love to her. They have the same translation, both are consensual, but a man would be called a pig for using the first one. The only exception is that makin' love would be used in a more stable relationship (you know, the kind that last for about 2 months) when fuck usually depicts a one night stand. Yet, another example to show how people are offended by words and not what they are actually saying.
Man: Do you know karate, because your body is kicking.
Woman: Oh, what a gallant gentleman you are. I can clearly see that you enjoy my personality and you are interested in getting to know me.
Man: Quite. after tonight's exertions, surely,you are in need of refreshment, my darling.
Man: Since we have known each other for so long, would you like to go back to my place and have some wild sex?
Woman: No, thank you, but I would like to make love.
Woman: Did you hear, I made love.
Woman's Friend: Oh, how romantic. How come I haven't met him.
Woman: Well, I'm still waiting for him to call. I think he might be the one.
Man: Hey guys, lets turn up our plasma screen bluray capable TV and watch the game.
Man's Friend 1: That seems like an appropriate way to express our masculinity. Let's also should loudly as we root for the home-team and bark in acknowledgement of the beer commercials referencing to how cold their beer is.
Man: perhaps we could exchange stories about our copious amounts of sexual partners.
Man's Friend 2: Indeed, you were telling me about that chick to whom you were makin' love about 18 days ago, but you didn't get the opportunity to complete the story because that one commercial came on about the cold beer.