Throne of Starlight : A Cursed Bloodline, Marriage of Alliance Fae Romantasy, livre ebook

The vines writhe away from her palm like startled snakes.
Rowena pulls back with a lacework of shallow cuts across her hand, blood welling in neat parallel lines. But where the thorns touched the faint thorn-shaped birthmark on her left wrist, they curled and blackened at the tips. She has never seen them do that for anyone.
Three nights ago, fae riders came through Thornwall village on horses made of smoke and ember, laughing like breaking glass. They took six people. Her brother Bram was the last, swinging a blacksmith's hammer at a fae lord's head until somebody put an arrow through his shoulder, and Rowena watched all of it from the root cellar.
Mira Greaves has survived sixty years on this border and lost a finger to a fae bargain. She tells Rowena what the birthmark means: the Thorn Curse answers to certain bloodlines, and hers is one of them. The same curse that is killing the crops. The same curse that put Old Man Harker in the ground with thorns growing out of his lungs.
*If I'm not back by dawn.*
*You won't be coming back at all.*
Rowena presses the birthmark to the wall, and the thorns tear themselves off her skin, and she steps through into furnace heat, black stone pillars, and a floor of crushed bone.
The man waiting on a horse of living ember is Dorian Flint, a thorn-hunter who tracks duskbloods across the Flame Court's border. His left hand is scarred and split, and something under the skin moves when the curse is close.
What Rowena offers is a bargain. What she gets is a contract sealed with her own blood, a brother in a cell three floors down, a slow poison already in her, and a deadline. *The poison is slow. You have three days to find the unraveling pattern.* She is a village scholar who reads botanical treatises and ledgers, and she has been handed a dead language.
Then there is Lord Croft, who led the raid, who traffics in people like her, and who wants something from her bloodline that no contract covers.
A fae romantasy of cursed bloodlines and forced bargains: a thorn wall, a hostage brother, a poisoned clock, an old text nobody alive can read, and a line in it about what the curse costs to end. The romance is closed-door.