This is neither a real story, nor does it Get Ethan Laid. But I did come across it while perusing mine own archives looking for an unrelated post, and it does Cross Ethan Over. More or less. ;-)
-- (Written circa July 2002, set... 5 minutes into the future?)
wolfling: There's also, not sure if this is a direct parallel but, Giles has Ethan and the Doctor has the Master? And am now whapping at the bunny that suggests an ethan/master as bad guys would be a good idea. (rolls eyes at self)
mpoetess: It would have to be comedic. i.e.
Ethan: Well, you buggered that up good and proper, didn't you.
Master: I have no idea what you're talking about. It was a brilliant plan.
Ethan: Oh, slipping the aphrodisiac into the wine for the feast was a great idea. Staying for the feast? Less so.
Master: I remained in the vicinity to make certain there were no unforeseen difficulties; anyone with a modicum of planning ability would have done the same.
Ethan: Bollocks. You stuck around to gloat, and see if he'd get blasted enough not to realize it was you when you offered him a shag.
Master: I certainly didn't!
Ethan: Right, so that was some other Time Lord disguised as a strolling troubador, making cow eyes at the Doctor while he sat at the King's right side and didn't drink the wine."
Master: Cow eyes? Rubbish.
Ethan: Look, there's nothing wrong with sticking round to gloat -- just admit you're sticking round to gloat. That way when they catch you, you'll look less like an idiot.
Master: I'm not speaking to you.
Ethan: Oh, you are too. Come on, I've got this great idea about spellhacking the Watchers' Council data library so that everywhere Rupert looks, he sees naked photos of me. You know you want to play.
Master: [Snort.] Hardly. Why should I assist you with your petty schemes to annoy your ex-whatever-he-might-have-been? What's in it for me?
Ethan: I'll let you use the spell to play with Earth's international guided missile systems.
Master: That, my dubious acquaintance, is more like it.
Ethan: Right. Give us a kiss, then.