Court of the Undying Seasons

Sarah J. Maas meets A Deadly Education in A.M. Strickland's lush, queer YA dark fantasy novel.
In becoming a vampire, I'm less than a girl. And more.
Or maybe I'm becoming what I always have been, deep inside.
A blade.
When nineteen-year-old Fin volunteers to take her secret love's place in their village's Finding, she is terrified. Those who are chosen at the Finding are whisked away to Castle Courtsheart, a vampire school where human students either succeed and become vampires, fail and spend the rest of their lives as human thralls...or they don't survive long enough to become either.
Fin is determined to forge a different path: learn how to kill the undead and get revenge for her mother, who was taken by the vampires years ago. But Courtsheart is as captivating as it is deadly, and Fin is quickly swept up in her new world and its inhabitants - particularly Gavron, her handsome and hostile vampire maker, whose blood is nothing...