Severin was sold at nine. His mother signed the vessel contract with a cross, because nobody in the tenements behind the cathedral could write, and the clerk entered the boy as "Severin" because the ledger needed a name. The statutes on the humane employment of vessels promised him food, a bed and a cleansing once he could hold no more.
Magister Odo Rask bought the contract. He was a licensed arcanist who killed monsters for the river towns of Halmath. Villages paid him to clear flooded cellars, burned-out farms and barrows that would not stay shut, and Rask paid Severin in bread to stay close and take the taint of his spells. For eleven years Severin followed him through mines, fen villages and a monastery where the monks had stopped being monks. The corruption made his hands shake for days at a time, and after a few years he could carry more of it.
Rask taught him to read so he could understand his own contract, and later the spellbook, because a vessel who understands magic is less likely to run. Village elders who tried to pay less once the thing was dead taught Severin to word a contract. He picked up Dwarven from miners who hired them against whatever lived below the third gallery, Elven from a tracker who hunted with them for a season, and Fey and Jotun from the creatures themselves. He stitched Rask's wounds for years before he had to stitch his own.
Rask threw fire across a room and missed as often as he hit. Severin wanted his magic closer. He taught himself to pour a spell into the edge of a bastard sword and to raise a plate of force over his off hand when something struck back. Rask called it a butcher's way of casting, and over the years it worked better than his own.
In the winter of 2252 a fishing village on the lower river hired them against something that took the dead from their graves before the mourners had left. The villagers called it the Molter, because each time someone saw it, it wore a different skin. Rask went into the reeds after it alone at dusk. Severin found him the next morning, emptied and laid out like a body prepared for burial, and the Molter was gone.
Severin was twenty, and his contract ended with his master. He sold Rask's house to pay the cathedral for his own cleansing and kept the sword, the spellbook and the name. Since that winter he burns everything he kills and speaks the rites of Whrasta over it, because he has seen what happens to the dead that nobody burns.
For four years he hunted along the rivers on his own. Early in the summer of 2256 a boatman on Lake Terrinor told him about a passenger who had paid for the crossing west and whose skin, the boatman said, had not fit him well. Severin took the next boat. West of the Gray Mountains monsters, beastmen and worse stalk the wilderness, few people can kill them, and Accreton pays for the work.
He keeps a notebook of every creature he has killed: where he found it, what it ate, what it feared and what killed it in the end. The pages on the Molter fill a third of the book. Since the alchemist's shop in Accreton reopened, he has been buying silver salve and fire in flasks there and asking the apprentice how they are made.