Evil Emperor, Your Empress Is So Proper

She was the best mercenary of the 21st century, with a full range of top-tier skills. After transmigrating, she had a portable dimension and every kind of modern technology at her disposal. Her father doted on her, and her four older brothers spoiled her! Yet everyone knew her as a dimwitted good-for-nothing! A fool? A good-for-nothing? Perfect! He was a cultivation prodigy whose monstrous talent terrified the entire empire and continent. He was domineering and calculating, cold and merciless. But with her, he was utterly devoted, cherishing her with all his heart. (One-on-one romance, both leads are pure and devoted, with plenty of sweetness!)