The Diabolic by S.J. Kincaid, 2016 Simon & Schuster
In the distant future humanity has fled Earth and our solar system has destroyed itself while we travel the stars. The Grandiloquy have worked to keep themselves at the top of the social structure. Society has fallen into decadence while the common people, the Excess, struggle to support their lifestyles.
The rich and powerful have developed humanoid beings to serve many functions: brainless servitor, innocent sacrifices,k dangerous diabolics. The general population has been shoved aside as fodder. The Senator Von Impyrean purchases as diabolic for his shy daughter. Nemesis is a companion for Sidonia Impyrean designed to protect the heir. the two are bonded and grow together to become the best of friends.
After several years Sidonia has been taught how to fit into court life, Nemesis has learned the threats against her charge. Sometimes even parents could be a threat to a diabolic's charge and as families are torn apart by diabolics the emperor outlaws them. Sidonia refuses to kill Nemesis - her only true friend. The Senator and his wife decide to replace the diabolics corpse with a land-dweller dying from a plague.
The emperor becomes a threat to Sidonia and Nemesis latches into his recent actions as leading toward either his demise or that of Sidonia. When the emperor summons Sidonia to the capital in her parents' place the Senator and his wife see a danger in the summons. They send Nemesis in her place - against her own wishes and Sidonia's.
At the capital, Nemesis struggles to blend into the cruel and frivolous children of the nobility. Taking her cue from Sidonia and her compassionate nature. She befriends the daughter of another disgraced senator unintentionally when she is drawn into engineering a beast to compete. Rather than allow her creature to be murdered Nemesis saves him and keeps him as a pet. Her unconventional compassion catches the eye of the emperor's nephew and heir. The Crown Prince feigns madness in the hope of saving his own life: rumor indicates the Dowager Empress has engineered the deaths of all potential challengers to her son's rule.
Bringing Nemesis into his orbit brings her closer to the Dowager and her machinations. When Nemesis believes Sidonia has been killed by the emperor her training pushes her to avenge the loss or die trying. Something is not right in the diabolics which protect the emperor, but the prince steps in to draw Nemesis to his side and toward an ultimate confrontation with either his uncle or his grandmother.
The Empire is on the edge of annihilation and rebellion. Science has been outlawed in favor of religion, but the technology is dying without the ability to repair it. This results in rips in the fabric of space and further unrest. Nemesis enters the political game at the top with little understanding of how to play, but a desire to change the very rules.
Written for older teens and adults with rampant disregard for human life The Diabolic raises questions of what it means to be human. Nemesis questions her very purpose: if she isn't designed to protect why does she exist? This is a great read for those who enjoy elaborate world-building and sci-fi with a touch of romance.