Death March to the Parallel World Rhapsody, Vol. 13 (light novel‪)‬

A DEMON IN THE DUNES
With their rigorous training session behind them, Satou’s party is finally prepared to take on the tougher enemies of the Celivera Labyrinth. Never ones to shy away from a side quest or two, they also find a hot spring and open a Japanese-style inn on the spot. Areamasters and floormasters beware! This group is refreshed and ready for battle! Unfortunately, the opponent who finds them turns out to be someone nobody saw coming…