The Runaway Princess is a drama, romance, and action visual novel following Salvius Valtieri, the heir to a powerful mafia family, who was secretly raised undercover within a rival gang. There, he encounters the player character, a spoiled and defiant princess who becomes his unexpected match. As their paths intertwine, a tense and passionate relationship develops, leading to a marriage that binds them together in a dangerous world of power, loyalty, and shifting allegiances.