The mc is a noble lady who is extremely smart but is considered vicious by the public. There was a wedding invitation from a noble from another country who is seen as a monster. The mc is currently engaged so the younger sister (she is a swordswoman and is well-liked by the public) has to take the place but because the younger sis was completely against this marriage the mc cancelled her own one to get engaged to the supposed monster.
The mc is a noble lady who is extremely smart but is considered vicious by the public. There was a wedding invitation from a noble from another country who is seen as a monster. The mc is currently engaged so the younger sister (she is a swordswoman and is well-liked by the public) has to take the place but because the younger sis was completely against this marriage the mc cancelled her own one to get engaged to the supposed monster.