[ There's a beat of hesitation and he wonders how she knows. He never told her, did he? Couldn't have, the only one who really knew aside from maybe Buffy was Sam and that puppy is long gone. Just a guess, then. A lucky coincidence that leaves his tone somber. ]
I promise. If it goes wrong... and it can, then I'll make it quick. You won't even know it's happening. [ Another beat. ] I've done it before.