One night, after countless mornings of the boy waking up shaking and pale, and looking as if he had missed sleep entirely, she stayed up to see.
He wandered out into the hall from his room and she followed.
He sat against the wall, and she took her seat besides him, neither acknowledging the other.
She turned, quirking her head, as if to ask, "Well?" But suddenly, what could have passed for a ghost glided down the hall, singing Christmas carols in a raucous yet spectral tone. Her mouth formed a soft "O" of understanding.
It was many nights they sat, or sometimes followed, the ghost of the past. He wasn't a ghost, really, but a collection of preserved incidents. His spirit was trapped inside his hated house, but at least the two living ones could be glad he seemed happy.
They never spoke of what they witnessed during the day, or indeed, during the night. Seeing him struck some fear into their hearts. If the past would remain forever, how could they ever hope to overcome their evils, the evils of the world?
They just followed silently, trooping up and down staircases, through hallways, into dusty rooms. Close together and never speaking.
It was one night, standing in the great, cavernous dining room that the girl summoned her courage, swallowed, and spoke.
"Hello, Sirius."
And the man, not quite anything of this world, turned slowly. And, just as slowly, a languishing grin spread over his face, and he winked.
"Hello, Ginny."
Harry and Ginny clutched each other's hands, watching Sirius wander away into another room. And they knew, after the wholly human experience of saying hello, that maybe Sirius wasn't so gone after all.
For the first time in a long time, a feeling of comfort descended over Number 12, Grimmauld Place.