A Contract with Eternity

He bought a thousand years of life. The price is the person he loves most, ten times over.
Novgorod, winter 1699. Andrei Lavrov is twenty-seven, a physician's apprentice who has watched fever empty three beds in a single week and who buried his mother after she drowned in her own lungs. Then a stranger who calls himself Kairos is simply sitting at his table, a black ledger open in front of him, offering a thousand years of life: no age, no sickness, no accident before his appointed hour. The price is ten payments, roughly one a century. Each time, Kairos will take the person Andrei loves most. Not chosen by him. Not surrendered by his hand. Just taken, quietly, as an illness, an accident, a war, until it seems as natural as weather.
Andrei signs. And so begins a life that stretches from Leipzig and Florence to Geneva and Kraków, and far beyond: a physician who cannot die, doing the life-saving, grief-studying work he swore he would, while the ledger waits patiently for the next name. Every love he allows himself is a debt he can already hear coming due. Every century he learns something new about what he has actually agreed to.
Along the way, he is changed by the people the bargain gives him: a woman who gives his grief a clinical name before the world has one; a psychiatrist who asks the questions he has spent decades avoiding; a boy whose life becomes the first real test of whether the ledger can be refused; and a woman who has lived far longer than any human should, and who knows exactly what the thousand years are for.
Kairos is the most terrible kind of antagonist: courteous, patient, and never once dishonest. He raises no voice and breaks no term. He simply arrives, on schedule, with impeccable manners, and asks Andrei to pay. What he wants, and what he is, is the question that follows Andrei across ten centuries.
A sweeping, intimate saga of love, loss, and the long work of going on - the story of what a human heart can learn to hold when it cannot look away from what it has agreed to lose.
If you love: immortal heroes and devil's bargains, sweeping stories that span centuries, tender and unflinching novels about grief, and love that costs everything - this is your next read.