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?!

It's been ten years since Rentt Faina, a down-on-his luck Bronze-class adventurer, set his eyes on becoming Mithril-class. Unfortunately, Rentt finds himself helpless when confronted by a legendary Dragon in the Labyrinth of the Moon's Reflection... and is summarily eaten. But Rentt has miraculously reawakened... as a Skeleton?!

If uncle tries, he can do anything! Uncle’s recollections of the otherworld are always unforgettable. Yet, few things have surprised Takafumi and Fujimiya as much as the revelation that the adventurer Alicia was a chosen hero straight out of fantasy! They say extraordinary things can happen when you believe in yourself, but could there be a deeper truth to Alicia’s role as a shining force for good...?

After Rentt senses something wrong with his familiar, Edel, he and Lorraine leave Hathara and return to the city of Maalt. There they find the city on fire and crawling with thralls. Rentt finds Edel safe beneath the orphanage and learns through him that a single vampire might be the cause of all the chaos. Just as Rentt goes out to help rid the city of the thralls, he runs into the last person he wants to see in this situation—Gold-class adventurer and vampire hunter Nive Maris!

Rentt meets a beautiful woman in the dungeon! What’s Lorraine gonna say?! After evolving into a thrall, Rentt explores an unmapped part of the dungeon and encounters a mysterious woman. In exchange for his discretion, she gives him a treasure called the Map of Akasha, but before he can learn anything about her, she warps him out of the dungeon. However, meeting her may just be the least of his worries. On his quest to become a Mithril-class adventurer, he must first pass... the Bronze-class Ascension Exam. His new life as an undead adventurer is finally beginning!

 By drinking a vial of vampire blood, Rentt Faina, undead adventurer, successfully achieved his next stage of existential evolution and has become a lesser vampire! Rentt, now short on funds, sets off on a journey to retrieve items required to craft equipment and weapons for his disciple, Alize. With his faithful mouse familiar, Edel, Rentt sets off to the New Moon Dungeon, slaying his share of forest wolves and lizardmen. But is he prepared for the legendary monster that's appeared in the labyrinth's boss chamber, in place of the usual earth dragon...? Meanwhile, a priestess-saint and Gold-class vampire hunter show up at the doors of the Stheno Company, where the sale of the tarasque is to be negotiated. But they're here for one reason: the suspicion that a certain adventurer is actually a vampire in hiding... An undead with a dream, eternally striving toward the rank of Platinum-class, even in undeath! All this and much more in the fourth volume of Rentt's undead adventures!