I though she become saint because misunderstanding after doing good deeds. Well, it's practically not a far. But still called by saint even after revealing her demonic form is surely something.
I can certain this village have rough future since we have two examples for that(it based on what I read so far, Tensei Akuma no Saikyou Yuusha Ikusei Keikaku & Henkyou-gurashi no Maou, Tensei Shite Saikyou no Majutsushi ni Naru)