Shiki (しき)

Crown Prince, Cecil, married Bertia who is a self-proclaimed "villainess." While they were enjoying their lives as newlyweds, Bertia received a request from her friend, Princess Risona of the Umube Kingdom, to produce her wedding ceremony. On their way to Umube, Bertia is being really excited, and Cecil has to support her... Source: Alpha Manga

Because Prince Cecil is extraordinarily intelligent, life is boring for him. His days are without much excitement, but he becomes engaged to Bertia, the daughter of a marquis. The first thing she says to him when they first meet is quite baffling. She claims she is the “villainous heroine” in the story of his life!! According to Bertia, she has memories of her previous life. In a certain “romance game” she played in her life before, she played the character of the “villainess.” Her purpose in her new life is to become an exemplary villainess and ruin the prince’s engagement. In order to achieve this goal, Bertia does one outrageous thing after another and brings chaos and confusion into his life. A unique “love” story with a twist!! Source: Alpha Manga