vega-ofthe-lyre:

“So. Are you proposing to someone?”
“I’m sorry?”
“I found this in your pocket.”
“No, no no, that’s, ah… a memory. A friend of mine, someone I lost. Do you… mind…”
“It’s weird, I feel… I don’t know, something.”
“People fall out of the world sometimes, but they… they always leave traces. Little things we can’t quite account for; faces in photographs, luggage, half-hidden hills. Rings. Nothing is ever forgotten, not completely. And if something can be remembered, it can come back.”
[Amy snaps the box shut and clears her throat]
“So was she nice? You friend?”
[The Doctor takes the box and briefly touches it to his forehead]

The Pandorica Opens; Doctor Who 5.12.