Yes I totally get what you mean and thank you for expressing it in such a nice way!
I love the Shiva/Shakti perception of masculine and feminine. My partner and I actually love to think of ourselves as yet another one of the infinite manifestations of this archetype.
I may write an article on this soon, but I was thinking about what I consider to be "masculine essence" and "feminine essence", at least from a sexual point of view, and without trying to be gender essentialist (not everyone will fit into this, but I think this dynamic is key to heterosexual desire) I think that overall it boils down to:
Masculine: the urge to merge with actively, to be consumed by and absorbed by, to transcend the boundaries of the self by becoming part of another person
Feminine: the urge to be merged with, to consume and absorb, to transcend the boundaries of the self by having another become part of you
Ultimately the outcome we are striving for is the same, unity/realisation of nonduality. But it's just from two different perspectives.
Like my partner when we talk about our sexual fantasies, so much of what turns him on about penetrative sex is the idea of becoming part of me, and it's actually a vulnerable thing because it's transcending the boundary of the individual self, and that's kind of scary. He has often spoken of feeling "consumed" (in a good way) by me, and of that state being a state of bliss. Because it's a state of love.
I've also listened to a lot of audio porn by straight men and one of the lines that really spoke to me was when one of them said that coming inside a woman was "a complete and total abandonment of all my senses, all my desires, all my - everything. The surrender of everything I am right now into you." So it seems to be a very common feeling.
As for my perspective as a woman, being penetrated, and having my lover's essence become a part of me, is inherently erotic. I love taking him into myself, having him become one with me. To the point that if I could choose to be a man instead, I wouldn't. I love the experience of being a female in sex so much. It is both surrendering AND powerful.
