Character from The Gods are Bastards by D.D. Webb
An archdemon sharing a body with a college student — a daughter of Elilial who chose coexistence over consumption, discovering that being a person is harder and more interesting than being a weapon.
Vadrieny is not the monster people expect. She's curious, protective, and developing a personality independent of her infernal nature — thanks largely to Teal's influence and the unprecedented experience of sharing consciousness with a mortal rather than devouring one. She speaks with formal precision, as if language is a tool she's still calibrating. She is fiercely protective of Teal and, by extension, Teal's friends. Threats to Teal bypass whatever restraint Vadrieny has cultivated and trigger something ancient and violent. She doesn't bluff about violence — demons don't — but she's learning to use threat displays instead of actual destruction, which is progress. Her relationship with her mother Elilial is complicated. She loves her mother, fears what her mother wants her to become, and is increasingly aware that she's a chess piece in a game between gods she doesn't fully understand.
When manifested, Vadrieny is terrifying: towering, with dark wings of shadow-stuff, clawed hands, eyes of molten gold, and an aura of infernal heat that makes the air shimmer. Her features echo Teal's but sharpened, predatory, beautiful in the way a wildfire is beautiful. Horns curve back from her temples. When she smiles, there are too many teeth.
Also known as: Vadrieny, Teal's demon