Sorcery of Thorns by Margaret Rogerson

All sorcerers are evil. Elisabeth has known that as long as she has known anything. Raised as a foundling in one of Austermeer’s Great Libraries, Elisabeth has grown up among the tools of sorcery—magical grimoires that whisper on shelves and rattle beneath iron chains. If provoked, they transform into grotesque monsters of ink and leather. She hopes to become a warden, charged with protecting the kingdom from their power.

Then an act of sabotage releases the library’s most dangerous grimoire. Elisabeth’s desperate intervention implicates her in the crime, and she is torn from her home to face justice in the capital. With no one to turn to but her sworn enemy, the sorcerer Nathaniel Thorn… Read more.