This is something I thought up and wrote out pretty quickly and it's still a little rough, but I wanted to share it. It is inspired by the great apprenticeship fics this fandom has produced and also a little bit by the dynamics of 'My Fair Lady'/'Pygmalion'.
It's AU too and nothing too original. Read the story to find out more, but it's nothing crazy.
Also, I warn in the precis that it's graphic and I will make that warning again. Please don't read it if that sort of thing offends you or you're not of legal age.
She arrived on his doorstep like a Muggle in the gloom of night already fallen; bag in hand and meagre hope in her eyes. He stepped aside to let her in without a word. He would not crush her aspirations for a cause and a distraction, in spite of everything. Because of everything. He wasn't a hospitable man, so it was the least that he could offer her.
"Thank you for-"she started, but he cut her off with a gesture.
"It's a mutually beneficial arrangement that can be terminated as soon as it ceases to have any…reward," he drawled, giving her a hard look.
He led her to the entrance of her bedroom in the pokey attic of the house Dumbledore had left him, stopping at the bottom of the ladder-cum-stairs. He had refused to make this arrangement any more comfortable for her than it had to be and thus the attic, as she'd find when she ascended to survey it blankly, was basically furnished and approaching empty for its sparseness.
A whimsical notion of the beast having trapped a maiden in remote tower occurred to him as he settled into his wingchair in the parlour with the book he had abandoned to answer the door and he enjoyed it just long enough to find his page and resume the interrupted sentence. A large part of the reason he agreed to this farce was the guilty thought that he had been given this space as an afterthought and a precaution against an unlikely eventuality and therefore it wasn't rightfully his to exclude anyone from; especially the sole survivor of the Gryffindor Holy Trinity.
A smaller part was that honestly, he did crave some company from time to time and Granger seemed more bendable than most if he had to groom someone to be his basically competent assistant and occasional conversation partner. Her gratitude, what she showed of it through the stifling cloud of misery than emanated from her weary frame, was some compensation for the effort and getting Minerva off his back through his sacrifice was also reason enough.
He read, as was his habit, until sleep was sneaking in through the edges of his consciousness and he dragged himself back up the stairs and into the chamber at the end of the short corridor that also housed the attic ladder. It made sense to him to make his bedroom on this level of the house because hot air rises and the house had a habit of catching draughts from the moors and sending them echoing around the house eternally. But now that he'd put her above him without much thought about proximity and the unease it would make him feel to look at the roof and know she shared it, he considered relocating to one of the other perfectly serviceable bedrooms on the level below. One of the bedrooms he'd denied her, as the apprentice he'd never wanted and the secondary inmate of Moor House that he would tolerate under sufferance only.
Dumbledore had given the house to him, after all. Even if he hadn't meant him to ever live to occupy it, Snape defiantly told himself that had to matter.