The library was large. Book shelves stretched up to the ceiling, honey wood polished and sparkling beneath warm, fluorescent lights.
Desks - a darker oak - were scattered across the room, hidden in the nooks and crannies, created over time by towers of books, piled when the shelves were full.
Cas loved it. Loved the smell of ink, and the crinkle of paper beneath her fingers. The warm, fuzzy feeling, of opening a new story, and falling in love with the characters - good and bad.
There were bullies in stories, but Cas always knew that they weren't real. That they couldn't kick, and punch and scream, and laughed when she cried.
No villain - however bad - could be as bad as her father.
Because once it was all over, he'd cry, body shaking with tears, as he crumpled on the floor.
And every time she believed him, forgave him, when he promised "Never again," until it was Again, and all promises disappeared like wisps of smoke.
Closing the book reluctantly, Cas slipped it back into the shelf, and crept out of the Library, giving a small smile to Mrs Pearce, who let her stay after closing time.
The old lady was strange. "It's the least I could do," she'd say, looking pointedly at Cas, as though they were both in on a secret, or maybe a joke.
An then blue eyes, hidden by spectacles, would cloud over again, and Mrs Pearce mouth would press once again into a thin line, as she was hurried out.
It was cold, the wind tugging at Cas's hair, and hissing in her ear. The sky was grey, and clouds twisted and spun through the sky - beautiful, but terrifying, and nothing like usual clouds at all.
It was raining, when she left the library, but now the rain had stopped - and it was like time had froze along with it.
The pressure in Cas's ears began to build, until it was a drum beat, constant and heavy, pounding against her scalp.
She slowly lowered to her knees, forced down by an invisible force, as a great figure swooped down from the sky - large and tall and terrible, swathed by dark grey rags.
Memories, only the worst, began to cloud Cas's head - hoarse shouts, and slaps, and broken bones.
She moaned, clutching her head, now curled in on herself. And somehow, when Cas heard a woman's screams, and saw a flash of green light - a single tear rolled down her cheek, for the victim she had never known.
Cas rolled over, lying defeated, almost offering herself to the thing, she recognized unconsciously as a predator.
Any release, from memories, would be nice. Not that they were all bad.
Cas remembered little things, like sunlight, and the library books, than even more - a rare day, when her father was happy, his breath no longer smelling of beer.
He'd gotten a job, high-paying for what it was, and took her to the park. They fed ducks, and even a swan, and ate ice cream, and nothing could go wrong.
Remembering, Cas felt a warm buzz spread across her chest, and an unexpected defiance to the creature leaning over her, and opening its mouth.
Something burst out of Cas, seemingly from her body, something large and silver and shining.
It charged for the creature, brave and furious, braver than Cas had ever been.
And with a mournful shriek the creature left, as though it had been burned by the silver thing's very touch.
"Thank you," Cas said softly, and the silvery animal - and it was an animal - bowed, before it evaporated into thin air.
The walk home was long, but Cas no longer jumped at every shadow, content in the knowledge of her silent protector.
And when she reached home - if Cas could call Spinner's End home - she smiled at her passed out father, and made her way upstairs.
She couldn't wait to tell Harry about everything