The Unwanted Undead Adventurer (Manga): Volume 8 (manga)

The last time Rentt saw vampire hunter Nive Maris, she warned him that vampires would soon attack the city of Maalt. Rentt begins to prepare for that possibility by collaborating with the adventurer’s guild, but Lorraine suggests he first find the source of his divinity—his strongest weapon against the vampires. They decide to visit the shrine in Rentt’s hometown of Hathara, where he got his first spark of divinity. Before they go, Rentt has to gather materials for Alize’s new wand. He goes to the New Moon Dungeon to do so and reaches a mine on the fourth floor.

However, once there he encounters something unexpected and legendary—an earth dragon!Rentt now has to find a way to come out on top against the dragon, or risk finding himself in the belly of a dragon for a second time!