Alexandra, a duke's daughter executed as a notorious villainess, somehow reincarnates as a cat. The one who picks her up is Ophelia, a marquis's daughter who is oppressed by her family. Touched by Ophelia's love, Alexandra learns to love a human for the first time. But Ophelia loses her life through the betrayal of her younger sister Helena and her fiancé, the third prince Vincent. Alexandra also dies alongside her, seeking revenge. However, Alexandra is reborn as Ophelia one year before her death――! "Ophelia, I will absolutely make you happy…!" To change Ophelia's tragic fate, Alexandra uses her innate courage and cunning as weapons, steadily trapping Helena and Vincent. Furthermore, Christophe, the prince of the neighboring Kingdom of Bessel, who approached Ophelia to use her, also falls captive to her before long...!? A magnificent doting × reversal romance, where a former villainess "kitty" changes the fate of the beloved owner she adores!