Holy fudging poop! That was intense, riveting, agressive, sexy, and so enticing. After reading the prequel "Make Me", I knew I was hooked and had to read the series.
Lovell is a skilled author who can balance the agressivitté of the story, whilst keeping it sexy and, yes, human. Una was conditioned to dislike any sort of casual human contact, and to believe that any sort of attachment is a weakness. In Kill Me, we slowly see her facade crumbling and how that terrifies her. Lovell gradually peels of layers of Una showing us what shaped her and how she is still indeed human.
Nero is just as ruthless as Una, and as of meeting her, he to looses grasp on his impassiveness. This makes for a very passionate, and dangerous pairing.
This was a prime example of how to write about organized crime and the feuds between organization, showing how calculated and two-faced everyone is, whilst remaining classy and protected - not an easy feat.