In a city where wealth runs on blood contracts, only Siren, a soul-summoning witch, can renew them. The Smith family mocked her and refused to kneel, and their contract lapsed, leaving them to a curse that consumed them within a night. Then the Browns came next in line and begged her to intervene. Siren agreed, switched on the Spirit Vein Lighthouse, then showed everyone her true power.
Arthur, the Brown heir, gives up his fortune, his name and his future to become her disciple. He climbs into her yellow taxi, and together they head into the places where black magic breeds. She is the master, he is the student, and neither is chasing power. They hunt the ancient evil that has been feeding on innocent blood. The road is long and the enemy is old, but Siren now has a driver, and Arthur has a purpose.
