I Should Be a Villainess Destined for a Break-Up, but the Cold-Hearted Duke Won't Break up With Me!

The plan was simple: play the foil, get dumped, live happily ever after. Now? The duke is head over heels for me, the world’s on the brink of war—and I’m going to die. I was reincarnated into the pages of my favorite romance novel. Not as the bright, beloved heroine, but as the cruel, grasping villainess, a mere stepping stone in the story. My only job is to dump the “Cold-Hearted Duke” so he can meet his true love. Fail, and war breaks out. I die. Nobody gets their happily ever after. Easy, right? Except playing a vindictive noblewoman when I’d been an ordinary woman in my past life is harder than it looks. Because if that’s the case, why—at the end of it all—is the duke holding me close, murmuring into my ear, “Grace… I will never, ever let you go”?! (Source: Cross Infinite World)