After being summoned to another world with her whole school of third years. Yoshihara Reina is like many students, deemed unneeded because they do not possess a hero title and are thrown out of the castle.
The once-popular girl is now surviving in the new world by working as a prostitute in the Halothane. The home of adventurers from across the continent.
In this world overrun by monsters... being an adventure is the most rewarding job, but also the riskiest. As a result, most adventurers pay a visit to brothels before going on a quest.
As the saying in Halothane goes... "Adventures start at a brothel."