This Will Kill That — Danielle K. Roux

District City is full of monsters. Not the kind that appear particularly vile from the outside. The kind who murder innocent people for no apparent reason. Abandoned houses are haunted by wayward spirits. Leaders of rival Colors clash over the secrets of a brutal past.

After the Plague thinned out the population, Rin Morana figured people would have stopped killing each other. No such luck. Her parents disappeared, and now she is set to take over as the new Lady Morana, head of the Green faction. To be a leader, Rin must contend with her relationship to her rival, Lady Amaya, as well as her own history of violence.

A series of riddles take Amaya Verity out of her isolated room in the Blue compound and into the hidden spaces of the City. Running away from captivity, Amaya takes shelter with Rin at the old Sydis house. There she meets two young men with demons of their own to contend with and abilities to match. Alan who is hiding out from his abusive ex, and Kazuki who might be the only person in the City that remembers the events of the Plague.

As they dig deeper, Amaya and Rin must decide whether to fight monsters or become them.