Diriel is a demi-demon who was soul-bound in The Edison Group's building by Samuel Lyle and knows all of their secrets. She states that her magic powers the Edison Group's building as well. She helped Chloe a few times, and in The Reckoning she helped Chloe Saunders and the rest of them escape in return that Chloe freed her. She still owes Chloe a favor, because she didn't finish helping them escape, because the demon lord over her came to take her away. She protects Chloe against a higher demon, when she brings up the Berithian Treaty which is a treaty between demons and necromancers, stating the demons can't woo young necromancers until they are ready to make their own choices with their gift.
She is described as having "scorching hot breath that smelled strangely sweet" and orange eyes the pupils slitted like a cat's.
She helps Chloe escape her room by possessing a Nick, a dead guard, and escorting her through the building.