Korosareta Oujo wa Hangyaku Koushakuka ni Shuushoku Shimashita

After realizing she had royal blood, Brigit's life was supposed to take a turn for the better. However, during her coming of age ceremony, she discovers that the royal family she so cherished only brought her back home as a sacrifice to further their own gains. With time wound back one year before her death, she must now uncover her ruthless family's plans and rewrite her twisted fate.

(Source: Tapas)