I am the older sister who was broken off from my engagement because I was not a true saint. Since I was banished, I was working as a herbalist in the frontier. Then, when it turned out that my younger sister, who was supposed to be certified as the true saint, had been committing fraud regarding her abilities, I was asked to come back, but...

"You are not the true Saint, but a false Saint. I will become engaged to the true Saint's younger sister!" With this declaration, my engagement was broken off and I was sent to the borderlands. I had become the Crown Prince's fiancée as a Saint, but one day I suddenly lost the ability to use my powers, and my younger sister awakened to the power of a Saint instead... Why did this happen? I was living in the borderlands under a different name as a medicinal herb merchant, but for some reason, a person claiming to be an envoy of the Crown Prince has arrived...