Vampire of Steel, Woman of Kleenex

In my teens I read an essay by Larry Niven entitled "Man of Steel, Woman of Kleenex." It was a very funny essay about what would happen if Superman should actually have sex with Lois Lane. Given muscles that enable him to "leap buildings in a single bound," the upshot is that if Clark Kent should do the dirty deed with Lois, when he comes inside her, it will blow her head off (and no condom in the world is going to prevent it).

I was reminded of this while reading Twilight and the subsequent books. In many ways, our lovable vampire Edward Cullen is a superman; I guess that's part of his appeal. Unfortunately, speaking as an SF writer who likes to keep his make believe internally consistent, I don't think Edward could be much of a lover. I'm just now to the point in the story ( in Eclipse) where Bella and Edward are talking about finally doing it, and I'm skeptical.

The vampires are described as being hard and cold and very fast and strong, with hearts that don't beat. But if Edward's heart doesn't beat, and blood isn't pumping, how the hell does his prime mover get hoisted into position? And it certainly won't throb. How do the hormones that make sex enjoyable move around in his body without blood flowing? And why should he still be interested in sex when vampires don't reproduce that way? Even if he can get it up, wouldn't it feel like getting poked with a cold pipe? And if he comes, will the frigid goo shoot right through his beloved Bella?

I'm sorry, but you Edward fans have to face it: unless Bella is into fetish quickies with an anatomically correct, refrigerated, animated mannequin, sex with Edward is better imagined than had.