Darien Cassel is one of the protagonists of City of Gods and Monsters and Loren’s love interest. Darien is a hellseher, an immortal with the power to use his magical Sight to track people, particularly those he can visualize via a photograph or other image. Darien works as a Darkslayer, or a member of hellseher groups that take on bounty hunting assignments for money; he is the leader of the Seven Devils, an elite Darkslaying group. Darien is close with the other Devils, one of whom is his sister, Ivyana.

Darien has a complicated relationship with his father, Randal Slade, who is the powerful leader of all the Darkslaying circles in Angelthene. Randal was both physically and emotionally abusive to Darien and Ivyana’s mother, a human. Though Darien’s mother reportedly died by suicide when her twin children were teenagers, both Darien and Ivyana suspect that she was actually murdered by Randal. Darien hates his father, but he also fears that he is dangerously alike Randal. This leads him to spend much of the novel pulling away from his attraction to Loren, as he worries that loving her will put her in danger, as the relationship with his father did to his mother.

Darien fears that his history of violence and drug use will “taint” Loren, whom he sees as innocent and pure. Darien’s history intersects with the theme of The Mortality of Hunting the Guilty, as he feels no qualms about hurting those who hurt the innocent, but feels morally bound to protect those who do not deserve to face the darker sides of Angelthene. It is this determination that leads him to protect Loren in the first place. Darien is ultimately unable to see himself as deserving of romantic love until he kills his father, something that causes him emotional pain but not regret, as Randal poses a threat to Loren. Though Darien previously feared that killing his father would cause a war between the different factions of Darkslayers in Angelthene, Randal’s efforts to kill Loren in the false Arcanum Well cause him to see his father’s death as necessary and worth the cost of a potential war.

Darien also embraces The Value of Mortality after he faces certain death in the novel’s climax. He realizes that the most important thing to him is seizing the time that he has available with Loren (and with his family and the city of Angelthene, to a somewhat less urgent degree) and that any objections he has to their relationship are minor in contrast to that. He takes this ethos forward after Loren’s magic resurrects him following the explosion of the city.

Darien’s personality combines stoicism, volatility, and deep-seated protectiveness. Outwardly confident and physically imposing, he often conceals self-loathing beneath dry wit and an insistence on control. His composure can border on emotional repression, but flashes of warmth—particularly with his sister Ivy or his Familiar Spirit—reveal a tenderness he struggles to express directly. Darien’s loyalty is absolute, sometimes to a fault: Once he chooses to protect someone, he will do so at any cost. He distrusts authority and resents moral hypocrisy, which contributes to his aura of rebellion within the rigid hierarchy of the Darkslayers. What most distinguishes him, however, is his capacity for change. Over the course of the novel, he evolves from an emotionally isolated weapon into a partner capable of vulnerability and trust, suggesting that redemption in Angelthene begins with self-awareness.

Dallas Bright is Loren’s adoptive sister and closest friend. She is the biological daughter of Loren’s adoptive parents; though Dallas has also been relatively neglected by her busy parents, she has gotten more support and attention than Loren has. This unequal affection from their parents didn’t drive a wedge between the two sisters, who rely strongly on one another for emotional support. Dallas initially grows jealous when Loren develops a romance with Darien, as she feels as though this is tantamount to being abandoned by her sister. Ultimately, however, Dallas forgives Loren and the two reconcile. Loren and Dallas also briefly argue when Loren accuses Taega, Dallas’s mother, of being complicit in the plot to kidnap various citizens of Angelthene, but Dallas comes around to believing Loren, even though they ultimately discover that Taega is innocent and has been falsely accused of crimes that she did not commit.

Dallas dreams of being part of the Aerial Fleet, the same military sect in which her parents have risen high in the ranks. During the novel, she begins to train as part of the Fleet. Dallas is sexually open but emotionally reserved; she quickly begins a sexual relationship with Max, one of the Seven Devils, but doesn’t agree to a romance with him until the end of the novel. At the end of the text, she and Max commit to one another despite Dallas’s reservations.

Randal Slade is Darien’s father, the leader of the various Darkslayer factions in Angelthene, and one of the major antagonists of City of Gods and Monsters. Randal is not initially revealed to be Darien’s father; Loren first learns of Randal as the head of the Darkslayers and learns of Darien’s father by his abusive reputation, only realizing that the two figures are the same when she meets Randal and notes his resemblance to Darien.

Randal was an abusive parent to both Darien and Ivyana, and the twins suspect Randal of having murdered their mother, though she allegedly died by suicide. Darien has long desired to kill his father, but he fears that a war would ensue, given Randal’s many powerful allies. Randal suffers from the Tricking, a degenerative disease that comes from overusing magic over time. This illness leads Randal in his search for the Arcanum Well, which he believes will cure him of the illness. Randal is ruthless in his quest to find the Arcanum Well. Randal traps Darien into a binding magical oath that will kill him if he does not find the Well; Darien is only freed from this oath when Randal dies. Randal also tortures Loren in an effort to force her to power the false Well, which ultimately fails. Darien tricks Randal and his allies into going into a house where a murderous demon is trapped, which results in Randal’s death.

Randal embodies the novel’s interrogation of corrupted authority and inherited violence. As both patriarch and political leader, he collapses the boundary between domestic and institutional tyranny, turning familial care into domination. His degeneration through the Tricking externalizes the moral decay that accompanies the pursuit of limitless power. In contrast to Darien’s eventual recognition of restraint as strength, Randal’s addiction to control highlights the cost of refusing mortality or moral limit. He thus functions as the narrative’s cautionary mirror for Darien—an image of what power becomes when stripped of love and empathy.