Shen Wan, a cannon-fodder character who has transmigrated into a novel, is doomed to die from the very start! She jumps into a lake to survive, only to accidentally swap souls with Pei Yuan, the cold-faced Prince of Zhenbei, feared as the King of Hell! From then on, they are forced to switch bodies every three days! In the prince's body, she sways her hips and dances, flirts with the Crown Prince, and confesses her love to herself in front of all the officials. In her body, he tears apart fake sweethearts and wipes out assassins. One recklessly ruins their reputation, while the other desperately tries to restore their dignity. Until the entire capital discovers that the cold-faced King of Hell, who kills without batting an eye, seems to be getting more and more adorable. What on earth is going on?!