"Spiritually, Adam was not very bright." ROTFLMAO!!
Thank you, LRichard, for another enlightening and entertainining viewpoint.
I'm sure Thirteen will be back with an answer, but in the meantime I thought I'd offer my own quick toonie's worth.
Off the top of my head, cards in the RWS deck that speak to me directly about sex and sexuality are the Devil, the Empress, the Tower, the Knight of Wands, the Knight of Swords, and the Ace of Wands.
Indirectly, depending on other cards in context: all the Wand Courts, all the Knights, the Three of Cups, and the Lovers.
To me, generally speaking, the Lovers tends to be about "choice of the psyche" along the same lines as Thirteen described. However, I think it can also indicate the type of sexual attraction between two people that not only never dies, but actually increases over time. That, in itself, suggests a karmic bond of sorts, though it doesn't necessarily mean the two people will get married or otherwise be together in this lifetime.
Just my twos, of course.