Ripon in 1624 was a cathedral town that had lost most of its wealth and kept most of its pride, and it was there, in a narrow house near the market place where the horn was blown each evening, that Mercy Thorne was born. She was the youngest of four children of Ross Thorne, a ferryman of the House of Thorne who was known to the hunting families as The Dry Ledger, and Katherine Proctor, the York clerk's daughter who was known as The Plague Clerk. Both parents were slayers. Neither made much fuss about it, and in the years the girl was small the household was a strange mixture of river work, paperwork and secrets kept from the neighbours. Her brothers Henry Proctor, born in 1618, and Leonard Proctor, born in 1621, and her sister Rosamund Proctor, born in 1623, had all arrived before her, and she grew up as the last and the smallest, the child the others were always being told to mind.
Her earliest memory, so the family said, was of her father's funeral. Ross Thorne died in 1628, when Mercy was four, and the picture that stayed with her was not the coffin but the river, grey and slow, and her mother standing at the water's edge writing something in a small book. Katherine Proctor lived on until 1636, and in those eight years she raised four children on very little money and a great deal of stubbornness. She taught them the alphabet from the ledger's own pages, and she made them learn by heart the names of the Proctor hunters going back to Walter Proctor in the fifteenth century. Mercy could recite the whole list at seven, in the order of the tally, without a mistake. It was not a gift she enjoyed, but she never forgot the pride in her mother's face.
Katherine's death in 1636 left Mercy an orphan at twelve. The older children did what they could. Rosamund, the practical one, took her into service and taught her to sweep, to mend and to hold her tongue, and for a year or two Mercy lived under a roof not her own, learning the routines of a household on the road. Ripon was a town of innkeepers, saddlers and dealers in spurs, and a girl with a neat hand and a good memory could be useful to any of them. She learned to serve at table, to count change quickly, and to write a fair bill. What she did not learn was to be humble about it, and more than one employer sent her back with a note saying she was too sharp for the post.
The civil wars overtook her in her late teens. Ripon lay on the great road north, and armies passed through it in both directions. Her brother Leonard had by then become a vampire slayer, and the shadow of his work fell across her days. She saw him come home muddy, silent, and once with a bandaged arm he would not explain, and she understood that the family business had not ended with her parents. She wanted no part of the hunting itself. She had a horror of blood, and she said so plainly. But she was proud, in a quiet manner, to be Thorne and Proctor together, and she followed his hunts through the small marks in the family record, the entries he sent home from the moors.
She married a shopkeeper, and the details of that marriage the family preserved only in outline. He was a tradesman of Ripon, respectable and steady, who kept a shop on the market square that sold everything a household might want: cloth, thread, candles, salt, nails, paper, and in season the sweet things that came up the road from the coast. Mercy, as the shopkeeper's wife, ran the counter and the books, and it was said in the town that the business had never done so well as when she began to keep the ledger. There were no children of the marriage. The family remembered that she treated her sister's boy, Ross Proctor, as nearly her own, and sent him packets of ribbon and sugar plums each year at Christmas.
The shop was not merely a shop. Ripon's market brought in country people from twenty miles around, and shopkeepers, of all people, hear things. Mercy learned to listen to the talk over the counter and to weigh it as she weighed sugar. A farmer's wife might mention that her husband's flock had been found lifeless without a mark upon it. A carrier might complain that a certain stretch of road was avoided by the local men after dark. She wrote these things down in the back of the shop book, in a hand only she could read, and when Leonard came through town she passed him the pages. She kept no official ledger, as she was never a slayer, but the White Ledger keepers learned to send their questions to her, and she seldom failed them.
Her relations with the rival family were, as far as the record shows, entirely civil. Mercy was the sort of person who could not be provoked into a quarrel over old grievances. She knew the story of Towton and the vampire the ledgers call the Guest, and she knew that Lancashire blamed Yorkshire and Yorkshire blamed Lancashire. She once told a customer, who had asked her opinion on the matter, that a tally was a poor thing to fight about when the fighting was so poorly done. It was repeated in the family for generations. She also refused, firmly, to hear anything against the Faulkners at her own table, a rule which caused some awkwardness in the household of a Proctor cousin and a good deal of amusement in the household of a Faulkner one.
The great plague year of 1665 passed her by, though she closed the shop for six weeks and lived on the stock she had put by. She outlived her sister Rosamund, who died in 1674, and she was in her sixties when the Glorious Revolution changed the country's kings and hardly anyone in Ripon noticed. In 1693 a fever came through the district, of a sort that the older people insisted on calling the sweating sickness, though physicians had long said the old sweat had gone. She was sixty-nine. She died that same week, in the room over the shop, and was buried in the churchyard within sound of the cathedral bell.
Mercy Thorne has no hunts to her name, no alias and no craft. What she left was a shop book, a small stack of notes, and a reputation for memory and fairness that the White Ledger keepers treasured. In the Slayerverse she is a reminder that the work of the slayers rested upon a wide web of ordinary people, and that a shopkeeper's wife in a Yorkshire market town, listening carefully, could be as valuable to the tally as any hunter on the moor.