The Ruler Of Darkness - Chapter 6Book 5:

What the heck? She, a famous doctor from the 23rd century, turned into a village peasant girl of a different world!

This book is about how a famous web writer who specializes in doting genre falls in love with a Mr. cellophane writer who specializes in angst genre.

- Description from Novelupdates

In a Fantasy world in which a young girl with the Divine Protection of the Hero battles against the Demon Lord. In that world, Red, the elder brother of that young girl Hero, possessing the Divine Protection of the Guide which only grants a high initial level, fought in the initial party of the Hero.

She is the slow-witted idiot of the Prime Minister’s Residence. Everyone bullies her. He is the most respected and unfeeling Prince, with frightening ability and absolute envy! Together, they are conferred an imperial edict of marriage.