The Scarlet Throne by Amy Leow

A dark, heart-thumping political epic fantasy by debut author Amy Leow—full of scheming demons, morally grey heroines, talking cats, and cut-throat priests, this delicious tale of power and corruption will captivate from beginning to end.

Binsa is a “living goddess,” chosen by the gods to dispense both mercy and punishment from her place on the Scarlet Throne. But her reign hides a deadly secret. Rather than channeling the wisdom of an immortal deity, she harbors a demon.
 
Though, one cannot remain a living goddess forever. When her temple’s priests decide that Binsa’s time in power has come to an end, a new girl, Medha, is selected to take over her position as goddess. But Binsa refuses to be discarded into a life of uncertainty as a young woman, and she strikes a deal with her demon: She will sacrifice her people’s lives in order to magnify his power, and in return, he will help her seize control from the priests once and for all.

But how much of her humanity is she willing to trade for the sake of ambition? Deals with demons are rarely so simple.