Betabore No Kon'yakusha Ga Akuyaku Reijou Ni Sare Sou Na No De. summary:

Elizabeth is devastated, her engagement was broken with the exact same lines as the scene in *The Holy Maiden Makes the Stars Fall in the Night Sky*, a popular novel among the nobility. Just as she’s about to explode in anger at the villainous heroine grinning beside her, the crown prince turns around and begins to denounce the heroine actions against her? Actually, everything is in the palm of the Prince’s hand. - (https://ncode.syosetu.com/n2133gc/)