I was told i couldn't love you so i decided to love a cat

After her fiance was stolen by her younger sister, Countess Lisette was forced to marry, almost as if to get rid of her nuisance. Her partner was Albert, the younger brother of the king, known as the "misanthropic Duke with the Iron Mask." Immediately after the wedding, her husband told her, "I can't love you," and stood her up on their wedding night. Then, a black cat appeared in front of her!? Lisette, who loves cats, begins to spend time with the black cat that visits her every night, but as she becomes closer to the cat, for some reason, her husband's attitude also begins to change...