Kono Sekai wa Fukanzen Sugiru

Summary:

Nikola is just a village girl working at the inn...until the day dragons invade, and she meets Haga, a scholar of everything around him. He's a part of an elite society called "Seeker," created to address a series of maladies plaguing their usually peaceful world. But both Nikola and Haga have secrets they hide...ones that will change each other's very existence...