Prosper's Demon by K.J. Parker

In a world where demons and humans coexist in a delicate balance, a nameless exorcist finds himself entangled in a complex moral dilemma. Tasked with expelling a demon from the mind of a brilliant philosopher whose work could change the course of history, the exorcist grapples with the ethical implications of his actions. As he navigates the intricate dance between good and evil, he must confront his own beliefs and the true nature of the demons he battles, leading to a thought-provoking exploration of power, ambition, and the blurred lines between right and wrong.

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