Love

The person becomes, for a time, mereley his physical self and so absolves the painfulness of the existential paradox and the guilt that goes with sex. Love is one great key to this kind of sexuality because it allows the corpse of the individual into the animal dimension without fear and guilt, but instead with trust and assurance that his distinctive inner freedom will not be negated by animal surrender.

Ernest Becker, The Denial of Death

That doesn't sound so romantic, but it makes a lot of sense!
This would be written on a card sent to you with a human heart (B.S.)