Ihoujin, Dungeon ni Kuguru.

In this dark fantasy tale, an accident transports Souya to a parallel world filled with danger and mystery. On his quest to explore this uncharted land, he encounters a gaggle of quirky friends, like Mysranica, the god of deception and secrecy, and a pair of elf sisters banished from their forest home. Before he knows it, Souya is making rogue adventurers eat lead, beating up petty nobles, and taking on dungeons where death lurks around every corner!

(Source: Yen Press)