"It occurs to me that you could also hold the door while I go get Sherlock myself, but then I need a faculty note for leaving campus."

"I could provide one of those."

"If you prefer it that way around, can do. But you do have to hold the door slightly open or time pauses and then I will find it challenging to drive."

"I understand."

"Okay." She gets him a piece of paper with which to write her note.

It is a very official-like note.

"Put on something opaque and hop in, time's slightly of the essence, but it's positive exciting news!"

Well, in that case... he emerges from his crypt moments later wrapped in a blackout curtain.

"But what if he'd think it was funny? ...Also, the first thing I'd want to do if I met a genuine duplicate of myself is fight them and the second thing also starts with an F, that seems like relevant information."

"I fought him. He's good, he got the first possibly-lethal hit on me, and the third one too. You are of course welcome to do the same as long as you have the 'one of you is a vampire and the other is a trained assassin' safety lecture first. I might want to have a more detailed conversation about your other activity that starts with F. He's not a straight-up duplicate, he doesn't look anything like you and occasionally he is heavier on the insane midget bit. And if you determine to the best of your considerable ability that he'd be more entertained than insulted by it you can pass on the phrase."

"Can we have that more detailed conversation while you are driving, or should it and consequently the relevant activity wait?"

"Eh, probably depends on how detailed it gets and whether traffic decides to make my reckless speeding complicated. Anybody besides versions of you and possibly insane midgets this is likely to come up with?"

"Well. There was Tony," he says. "And, consequently, any version of him we might find. And, oh, I don't know. In the absence of constraints on my behaviour like 'this would upset Juliet' the list could grow to be quite large."

"Hrm. On reflection," she says, running a yellow light, "I can probably cunningly use my powers of self-hacking to avoid being upset by you going around performing actions brought to us by the letter F, and I would particularly feel like a jerk if you found an alternate universe Tony and I got in your way - Mark, the insane midget, predicted that one, by the by - but would probably feel more generally threatened by non-Tony entanglements that had high ratios of emotional affair to fornication. Aaaand would feel extremely awkward if you picked up, say, a demon that I later felt obliged to kill."

"I can't easily predict the emotional affair to fornication ratio of consorting with whole or partial duplicates of myself," he says. "But with non-Tony non-selves it's likely to be pretty low. I will do my very best not to pick up anyone you might want to kill later."

"Okay, Tonies and yous are excepted from the emotional affair clause. Although I envision myself becoming rather unbecomingly mopey if I want attention and you're routinely off elsewhere."

"I will endeavour not to amass a harem of Tonies and selves."

In goes blackout-curtain'd Sherlock.

"Hi Giles thanks Giles! Mark, Sherlock; Sherlock, Mark."

"Hello, Mark."

"Hello, Sherlock."