Who is Cabell Lark?

Cabell Lark is Tamsin's brother, though not by blood. Adopted by Nash due to his rare ability to see and redirect curses, Cabell thrives in the world of the Hollowers. This causes him to fight with Tamsin often, as she longs for stability. However, Cabell is cursed to turn into a hound whenever he loses control of his emotions. Over time, Cabell becomes more jaded with life and his situation, leading to him betraying the group to join Lord Death. Cabell claims that Lord Death showed him who he really was, but what this actually means is left ambiguous as Tamsin refuses to join them.