The phrase 어느 날 공주가 되어 버렸다 translates to "[One day, I became a princess](javascript:void(0))" in English. This phrase is the title of a Korean romance fantasy web novel and webtoon, which was originally serialized from December 20, 2017, to October 24, 2018, and published by 위치북. The story revolves around a girl who suddenly wakes up to find herself as a princess, but in a tragic twist, she is the doomed princess destined to be killed by her own father, the emperor. To survive, the protagonist must avoid drawing her father's attention and navigate a perilous fate in a fantasy setting filled with romance and magic. This novel has been adapted into an animation as well, which started airing in October 2025.
