It is surely the becoming of a person. Most of our being is at rest, unlived. In passion, the body and the spirit seek expression outside of self. Passion is all that is other from self.
Sex is only interesting when it releases passion.
The more extreme and the more expressed that passion is, the more unbearable does life seem without it. There is no end. There is no beginning. Somewhere that difference can be expressed. It is the highest order of wit, as it indicates the coolest yet quickest exercise of genius, at a moment when the passions are roused.