Clockwork Angel - Book 1 (The Infernal Devices) by Cassandra Clare

Magic is dangerous — but love is more dangerous still When sixteen-year-old Tessa Gray crosses the ocean to find her brother, her destination is England, the time is the reign of Queen Victoria, and something terrifying is waiting for her in Londons Downworld, where vampires, warlocks and other supernatural folk stalk the gaslit streets. Friendless and hunted, Tessa seek Magic is dangerous — but love is more dangerous still When sixteen-year-old Tessa Gray crosses the ocean to find her brother, her destination is England, the time is the reign of Queen Victoria, and something terrifying is waiting for her in Londons Downworld, where vampires, warlocks and other supernatural folk stalk the gaslit streets. Friendless and hunted, Tessa seeks refuge with the Shadowhunters, a band of warriors dedicated to ridding the world of demons. Drawn ever deeper into their world, she finds herself fascinated by — and torn between — two best friends and quickly realizes that love may be the most dangerous magic of all