Revenge with the Demon King

Everyone in the capital knew her as the fool and laughed at her ignorance. Her sister plotted against her and she was murdered at a young age. When her eyes opened again, she had undergone a complete transformation in her next life. She rules the world with her divine weapon and her adorable pet can subdue all beasts. He is a bloodthirsty and cold-hearted man. When he awakened, he pressed himself against her and whispered, "I've waited centuries for you. How are you going to repay this favor?" Her features are stony as she declares seriously, "I'll send you to your death. Are you wiling?"