The Unwanted Undead Adventurer (Manga) Volume 4 by Yu Okano

After Rentt, the undead adventurer, passes his Bronze-class ascension exam for the second time, Sheila becomes suspicious and uncovers his true identity. Despite playing dumb, her sincerity convinces him to tell her everything. Now a Bronze-class adventurer again, Rentt takes a special job from an orphanage for a single bronze coin. But before he can fulfill the dangerous and difficult request, he somehow gains a vampiric servant of the rodent kind. In the fourth volume of this adventure fantasy, can Rentt survive his journey into the poisonous and treacherous Tarasque Swamp?!