After Becoming the Gu King's Wicked Fiancee

I transmigrated into the Miaojiang villainess from my own novel, and from the start the Gu King was gripping me by the throat and forcing me to swallow a truth-telling Gu. He said he would kill me in seven days. I said fine. But I didn’t tell him I could understand his Gu snake when it shouted, “He’s lying.” I’m the fiancée he hates with all his heart, the one responsible for his sister’s disappearance. He spared my life only to torment and use me. But every time he tries to kill me, his hand trembles; Every time he gives me medicine, there’s a piece of candy beside the bowl That’s when I know I’m bound to win this game.