While it seems simple my understanding of essence as it relates to gender is our experience is very yin yang. I was born with a dominant Mother and a dominant twin sister and have shared fantasies about becoming my wife's slave. I believe myself to be very feminine with biological attributes that are female, and a consciousness that is emotional If not sensative.I believe essence to be very much like a positive or negative charge that male and female existed long before the concept of humanity. I have lived through what I was intended to live through on the male spectrum, and have reconciled with my inner conscious as being of a primarily female essence.
Biologically, male and female has existed long before humanity. I wouldn't say they are complimentary opposites, though. Males and females have far more in common than they do in difference. Yin/Yang is symbolic and incorporates ideas that in my opinion have more success describing the laws of physics or the nature of physical forces than they do men and women.