Maybe the function (or one) of the female orgasm is to provide stimulation to the man’s penis, drawing out of him the Divine Fire energy he needs to accumulate in order to give as much of this Fire to the woman, as much as she needs to receive. (I am assuming here that the couple is practicing some method of Tantric sex and not just brute, animal-like physical fucking.) It is a pleasure for both partners to be channels for this Divine Fire, for it is a Divine Emanation straight from Source, from the Universal Spirit. It is God at its Finest, its Subtlest. It is LOVE.
This is why the ego-mad people of the western world tell us sex is bad. Because their Egos know what they have forgotten, namely that Sex can lead to a powerful Union with Love, which is God manifested. Union with Divinity thru Sex. The ego doesn’t want this, hence the ego-controlled masses of the world are afraid of this one spiritual practice that could ironically lead them to the joyous realization that God is within.