FicWad

I like this story - there's a good sense of "arrogance" in the air, mixed with a reasonably well written usage of metaphors and imagery.
I particularly liked the parallels between Lex and Clark (as in how he would become Superman, flying, etc), but I personally didn't care for the crude wording at the very end.
But I should warn you, I'm not such a fan of explicit sexual fiction, so if you're okay with that, then it's fine.
On the other hand, the same feel could perhaps by achieved using a different word, a metaphor perhaps, or more simple: "Lex's tongue and Lex's body".
As a standalone story, it works just fine - if you want it to be a prologue, I'd suggest expanding it just a little.

Otherwise, good job!