Youhei to Shousetsuka

With the advent of the transcontinental railroad, smoke from steam locomotives veils the cities and mercenaries are a thing of the past. Sword, a mercenary, is down on his luck when he accepts a job from the bestselling lady novelist, Verderon. They set out on a journey to a dangerous, uncharted mountain... Only to be caught up in a conspiracy between church and state?! A tale of iron swords and typewriters!

(Source: Manga UP!)