The Familiar (original) Leigh Bardugo

shabby house, on a shabby street, in the new capital of Madrid, Luzia Cotado uses scraps of magic to get through her days of endless toil as a scullion. But when her scheming mistress discovers the lump of a servant cowering in the kitchen is actually hiding a talent for little miracles, she demands Luzia use those gifts to better the family's social position.

What begins as simple amusement for the bored nobility takes a perilous turn when Luzia garners the notice of Antonio Pérez, the disgraced secretary to Spain's king. Still reeling from the defeat of his armada, the king is desperate for any advantage in the war against England's heretic queen—and Pérez will stop at nothing to regain the king's favor.