Angelica Rapha Redgrave is the daughter of Duke Redgrave and the former fiancé of Prince Julius Rapha Holfort. In the original otome game, Angelica was the first antagonist.
Angelica originally was supposed to be very hot-headed which would be her eventual downfall but because of Marie, we get to see more of who she is.
An example being her feeling like a failure when Julius became infatuated with Marie, causing her to break the vase in her room and cry from her rejection from the prince.
After the duel with the Prince, she has shown to be far more kind and humble.
(Source: The World of Otome Games is Tough for Mobs Wiki)