elise the great posted:

Male elves achieve erection by external constriction. To have sex, they need some biological equivalent of a cock ring. Whether their penises are "innies" or just flaccid except during intercourse, they are incapable of restricting venous return on their own... and yet the elven vulva must be compatible to some degree with penetration, or else man/elleth coupling wouldn't produce offspring. One may, if one is willing to consider extreme possibilities, entertain the idea that the elven vulva may exhibit some mechanical trait that assists the ellyn in achieving erection by constriction, by restricting venous return through strangulation.