After her classroom explodes, a high school girl awakens to discover that she has been reborn as a spider. Hungry, she searches for something to eat.
After undergoing some changes, the spider weaves a comfy home for herself. But when some uninvited guests arrive, she determines to get stronger.
The spider's newfound confidence is soon dampened when she encounters some human adventurers. Later, the students take a magic lesson in the woods.
As the spider explores the lower levels of the labyrinth and gains new abilities, a mob of monkey-like monsters threatens to stop her progress.
Having escaped from the magma area, the spider decides to evolve before choosing a new ability to learn. A particularly odd skill piques her interest.
Shun's brother Julius and his party venture further into the labyrinth on their hunt. Meanwhile, the spider takes on a powerful eel-like lava monster.
Katia, Shun and Fei learn that there are some reincarnated classmates still unaccounted for. Later, the students undergo training in the mountains.
As his friends discuss the ramifications of the assassination attempt, Shun thinks back on his former life. The spider takes an interest in magic.
The hero Julius shares a brief reunion with his brother Shun before announcing that he must head to the Empire and deal with a growing demon threat.
The spider briefly ponders her interaction with the powerful Overseer D. While visiting his family, Shun receives a difficult command from his father.
Armed with a startling amount of new information and determined to save the world, the spider sets her sights on defeating the Earth Dragon Araba.
The spider dodges the Earth Dragon's barrage of attacks before luring it into a painful trap, but her opponent is more resilient than she thought.
Finally reaching the surface, the spider aims to evolve into a more human-like form. Shun and his family meet with the elf chieftain to discuss war.
When a group of bandits attacks a carriage carrying a couple and their child, the spider intervenes to save them. Shun experiences an awful betrayal.
Having formed a mental link with the Queen Taratect called Mother, the spider's parallel minds grow concerned that she hasn't fought back yet.
The mysterious administrator D contacts the spider again to congratulate her on her evolution and provide some enlightening answers to her questions.
While resting in the labyrinth, Shun and Filimos listen as their guide tells them about his encounter with a particularly frightening monster.
The spider spots some suspicious figures following baby Sophia's carriage. Shun and his friends reach a kingdom whose people worship the goddess.
The townsfolk begin worshiping the spider as a divine beast. Arriving at the elf village, Shun’s party has a surprising reunion with a familiar face.
After encountering an envoy from the Kingdom of Ohts, the spider receives a sudden visit from the administrator Güliedistodiez, who has a request.
Joined by two new allies, Shun and his friends inspect the elves’ magic barrier. Later, Filimos reveals to them the existence of the administrators.
As the spider takes advantage of the war between Ohts and Sariella to gain lots of experience points, Ariel suddenly appears on the battlefield.
At the climax of Shun and Hugo's battle, Sophia appears before them. Shun and his friends attempt to fight her, but she easily deflects their attacks.
Having escaped danger by laying eggs, the spider evolves into a more familiar form. Shun clashes with Wrath, his best friend in their former life.