Burnout, by LabRat. It's Eghart's (spelling??) fourth law: "When two heavenly bodies collide, clothing just gets in the way." Clark uses it as a way out when Lois demands to know how he removed a certain garment from her without disentangling their bodies. Steamy and sensual scene, and yes, I still know Burnout by heart, I know.
Kaethel
(heading back to work :p )