The Villainess and the Demon Knight Novel Volume 1 was written by Nekota with illustrations by Asahiko.

Being reincarnated as an otome game villainess is hard enough, but fate sure didn't hold back on stacking the odds against Cecelia. Her engagement is broken off, the heroine is harassing her, and she's forced to work in a brothel! To make matters worse, her first customer is none other than the heroine's childhood friend and debaucherous leader of the Imperial Guard, Duke Lucas Herbst. Terrified, Cecelia finds herself relentlessly pursued, only to wake up the next day in his mansion—marked as his fiancée?! Bound to this unhinged knight, the troubled villainess must endure his obsessive love. But is his intoxicating affection a curse…or is it a blessing in disguise?