The circumstances (memory-lossed friends, last of their kind, etc) sort of matched up.
And thank you, so much. Here it is.
-------
Will recognises the sound from the Book of Gramarye, but it takes him a moment to place it, time enough for the blue box to finish materializing and eject its occupant, messy-haired and babbling at the speed of light.
“ -- You wouldn’t have felt it, of course, Donna, but anyone time-sensitive would have noticed the disturbance, I mean, a whole race -- ”
He sees Will and stops, startled. “Old One,” he says, after a pause.
“Time Lord.” He inclines his head slightly.
“And this is Donna. Donna, meet -- ” He glances to his left and visibly deflates. “Oh. Right. Gone.” His smile is brittle now, broken. “Alone again.”
His eyes are sad, Will finds himself noticing, old and sad and heavy with the weight of the universe. He has never met the Doctor before, but he has heard tales, and the echoes of the Time War made their way even here, for all those sensitive enough to hear it. The Old Ones didn’t interfere, Earth-bound and preoccupied with their own, more understated struggle as they were.
At last Will says, uselessly, “Our battle with the Dark. That was the disturbance you felt. The Light and the Dark, and now they’re all gone and no-one remembers.”
“So you’re the last, then, too? All alone in the universe, just like me. At least your people left by choice.”
“Who is Donna?” he asks tentatively.
“A-- a friend. My best friend. She was brilliant.” The grin wavers helplessly, and then shatters. “She saved the world, you know. The universe, even. And then she had to forget, to save her life, and she can’t ever remember or she’ll die.”
“Simon and Barney and Jane and Bran -- none of them remember,” he offers, trust for trust, story for story. “And Bran, he chose to forget, to be human, and so it hurts the worst, with him.”
A bitter twist of his lips. “They always leave, in the end.” And then what Will now knows to be a mask slips back over the Doctor’s face, and his grins widely, invitingly.
“Well, Old One, what do you say? Fancy an adventure?”
----
Thanks again!
-Aila