COMPLETED
Thrown into another world
Saintess saving the world trope
FL accidentally ends up in another world (she literally drops from the sky) and recognises it as the world of a novel she read. She attempts to keep a low profile whilst working as a priestess healing others and peacefully wait for the ogFL to arrive and save the world. But then... he (ML) shows up demanding her powers.
This is an interesting webtoon with great characters!
My Red String of Fate