The Transmigrated Sweetheart Stole My Night

Seraphina made her name online debunking traditional medicine. During a livestream she was exposing a diet drug cut with aconite, and swore an oath about putting on two hundred pounds. The oath took. She woke in the Orendia Empire as an overweight illegitimate daughter who had been set up and disgraced, and was married off to Crown Prince Elias, who was being worked against by court officials of his own. She knocked Elias out, took him, stole his gilded badge and ran while pregnant. She hid at Black Crow Fortress, later renamed Holy Light Fortress, and made a living practicing medicine. Five years on she has two sons and a daughter and has lost the weight. The younger daughter, Leah, happens to save Elias when an assassin comes for him, which gives away who she and her mother are, and the prince finds the wife who ran.