The story follows the experiences of various characters across different locations, often involving dangerous encounters and personal growth.
In the capital city of Sternbelt, a weary traveler named Ys is ambushed by two petty thieves in a dark alley. Ys, revealed to be a skilled spy, effortlessly incapacitates them using his unique combat techniques, specifically "Poisonous Fist" and a hidden needle. He then proceeds to a popular inn, "The Goat's Haven," where he orders a meal. After dining, Ys enters his room and reveals a hidden passage behind a painting, leading to a secret underground base. There, he reports to his superior, Farg, a formidable half-fox, half-tiger warrior. Their discussion centers on a mysterious "Black Apostle Oni" who is believed to be responsible for the disappearances of numerous spies. As they deliberate their next course of action, a strange, slithering sound is heard, and they realize they are under attack by an unknown, dangerous entity, later identified as a mutated form of a "Zombie Snail." The creature, possessing unusual abilities, incapacitates Ys with paralysis and then attacks Farg, ultimately consuming him. Ys, despite his efforts, is also overwhelmed and consumed by the creature. He wakes up in his inn room, seemingly unharmed but with a mysterious scratch on his arm, hinting that the ordeal might not be over.
Meanwhile, in the Great Forest of Koudeln, an elderly High Elf named Schvels returns to his secluded elven village after a two-hundred-year absence. He had left his home to explore the outside world, becoming a successful merchant and starting a family. His return is motivated by a desire to check on his kin after a recent war. He is met by his older brother, Esseva, who conveys their father's dying wish for Schvels to return if needed. Esseva then takes Schvels to a hidden, heavily fortified hot spring resort called "Parabera Hot Springs," operated by friendly demons. Schvels is amazed by the resort's advanced facilities and the diverse clientele, including elves and demons. He also meets his niece, Mail, a skilled High Elf dancer, and learns about the resort's unique services, including massages that are surprisingly effective in promoting fertility, a topic that sparks a lively discussion between the brothers. Schvels becomes addicted to the hot springs and vows to return with his family.
Separately, a young adventurer named Beluf, accompanied by a skilled hobgoblin mercenary named Hobrai, ventures into a labyrinth. Beluf, though inexperienced, shows great potential and determination, aiming to become stronger. Hobrai, who is also developing a new line of potions, acts as both a combat partner and mentor. They face various monsters, including goblins and wolves, with Hobrai's advanced weaponry, the "Bone Nail Gun," proving highly effective. Beluf, despite his initial struggles, demonstrates bravery and resourcefulness, particularly in his combat against a wolf-like monster. He also learns the importance of using a shield, which he decides to rent from Hobrai's employer, the "Parabellum Trading Company." Their expedition is successful, yielding valuable loot and experience, and Beluf resolves to continue his training and exploration.
In another storyline, a group consisting of Al, his energetic half-ogre sister Auro, and other companions, embarks on an expedition into a "Fairy Playground" derivative labyrinth. Auro's reckless use of powerful magic, particularly fire-based spells, causes widespread destruction, including a massive forest fire. Al and the others struggle to manage the chaos and escape the escalating danger. They manage to defeat the labyrinth boss, but Auro's actions create significant collateral damage.
A separate narrative follows Kanon, a lone demon, as he delves into the uncharted "Demon's Cry Labyrinth." He faces formidable "Spartoi" monsters and utilizes a powerful relic, the "Axe-Ending Demon Spear," to overcome them. He discovers a hidden passage leading to a chamber with two powerful dragons, "Mithrilkyu Dragon King" and "Platyrbal Dragon King," which he narrowly avoids fighting. He then encounters a puzzle room and a sealed chamber containing a golden coffin and a statue of a demon, hinting at a significant discovery related to his clan's history and the origins of labyrinths. He retrieves ancient texts and powerful artifacts, including a diary that reveals the protagonist of the diary, Oberou, was once human but was reincarnated as a goblin and then evolved into a "Golden Yaksha Demon." The diary details Oberou's adventures and his acquisition of a unique "Divine Labyrinth" called the "Umbracem Parabellum."
Finally, a chapter describes a "Setsubun" festival, a bean-throwing event, where various demon and human factions engage in a playful battle. The participants, including Oberou and his family, are divided into two teams and use enchanted beans for the contest. The chapter highlights the close relationships and playful rivalries within the group. Another segment details the preparation for "Sweet Valentine's Day," where various female characters, including Kanami, create chocolates, with Kanami incorporating her own blood into her creation for Oberou. The chapter concludes with Oberou enjoying the chocolates, unaware of the true nature of Kanami's offering.
