In the Service of Hogwarts (слэш)

Two weeks ago, he'd been Harry Potter, unremarkable boy living with his aunt and uncle, notable only for the strange things that sometimes happened around him. Things he couldn't explain and didn't talk about.
Then a Ministry official had witnessed him accidentally vanish a pane of glass at the zoo, and everything changed.
"Underage wizard, fallen through the cracks," the woman had said, her wand already out to modify the Dursleys' memories. "Happens sometimes with Muggle-raised children. You should have received your Hogwarts letter at eleven, Mr. Potter."
"I'm fifteen," Harry had said stupidly.
"Yes. We'll need to sort that out."
OR
Harry Potter never got his Hogwarts letter.
At fifteen, he's offered a deal: three years of Domestic Service in exchange for a magical education.
Domestic Service means only one thing at Hogwarts, and Harry is about to discover what that is.