His Highness' brother's favorite: Even if You Reincarnate, You Can't Escape from Your Natural Enemy!? (Associated Names)

Ashley, a count’s daughter, has a memory of her previous life as a black rabbit of the demon kingdom. The king’s younger brother, the marquis, fell in love with her and became her fiancée. However, he’s a descendant of the brave hero who destroyed the demons…!? The story of Ashley, who looks like a rabbit…