The Last Bloodcarver by Vanessa Le

A pulse-pounding new YA fantasy in which "you’ll gasp, you’ll scream, you’ll cry, and you’ll be begging for the next book." (Chloe Gong, #1 New York Times-bestselling author of These Violent Delights)
Nhika is a bloodcarver. A coldhearted, ruthless being who can alter human biology with just a touch.
In the industrial city of Theumas, Nhika is seen not as a healer, but a monster that kills for pleasure. And in the city's criminal underbelly, the rarest of monsters are traded for gold. When Nhika is finally caught by the infamous Butchers, she's forced to heal the last witness to a high-profile murder.
As Nhika delves into the investigation, all signs point to Ven Kochin, an alluring yet entitled physician's aide. Despite his relentless attempts to push her out of his opulent world, something inexplicable draws Nhika to him. But when she discovers Kochin is not who he claims to be, Nhika will be faced with a greater, more terrifying evil lurking in the city's center...
Her only chance to survive lies in a terrible choice―become the dreaded monster the city fears, or risk jeopardizing the future of her kind.