[PatrickHenry]

Larry Niven. The piece was titled "Man of Steel, Woman of Kleenex."

Found it! Very funny stuff. Recommended: Man of Steel, Woman of Kleenex. Sample:

But with kryptonian muscles behind it, Kal-El's semen would emerge with the muzzle velocity of a machine gun bullet. (*One can imagine that the Kent home in Smallville was riddled with holes during Superboy's puberty. And why did Lana Lang never notice that?*)

[r9etb]

A classic. My favorite line from that: "... ripping [Lois Lane] from crotch to sternum, gutting her like a trout."