Re: girl orgamism
all it wants is for the species to prosper, so if sex feels good, then guess what? people will do it more and have more babies.
Scientist have reasoned that, humans enjoy sex outside of procreation in order to keep men and woman together, look at animals, they have to all fight for top position for the rights to mate, once the Alpha male is chosen, then he impregnates the females, after that, he is basically out of the picture until next mating season.
Baby humans need more care, so nature needs a way to keep the "father" in the picture, and by making sex enjoyable all the time, and having females that dont have to be in heat to enjoy sex, kinda solves that problem, by caring for their females and their children they are insured a future female that they donthave to fight for (again?) and sex whenever they want.
Its a lot more complicated than what I described, but you get the picture.
Another thing to keep in mind, is that inside the womb, or the uterus, we are all basically a lump of clay, until the hormones turn us into boys or girls.
So girls orgasm, because boys do--it is the same with male nipples before those hormaons are turned off(so to speak)