Synopsis: I Became the Villainess in a Disastrous Novel

As I delved into the pages of the novel, I found myself embodying the very antagonist within its plot, only to soon discover its resolution to be utterly underwhelming. Despite the painstakingly slow buildup towards the grand culmination of the empire's affairs, the climax was a mere blip as a demon rampaged on the wedding day of the protagonists, tearing everything apart in mere moments. It was time to toss aside this lackluster tale and focus on survival - I decided to flee to the neighboring country. But alas, just as I was about to make my escape, a man appeared before me with a grand proclamation: "For a century, I have waited just for you." Little did I know, Grand Duke Arvis, who had orchestrated the destruction of the very empire I sought to flee, was none other than the Demon King himself in disguise. He grabbed me with fervency, his gaze ablaze with raw emotion, "If you were to ever leave me, I'd obliterate this entire continent that dared take you away from me." This made no sense.