After dying a laughable and pathetic death on his way back from buying a game, high school student and recluse Kazuma Satou finds himself sitting before a beautiful but obnoxious goddess named Aqua. She provides the NEET with two options: continue on to heaven or reincarnate in every gamer's dream—a real fantasy world! Choosing to start a new life, Kazuma is quickly tasked with defeating a Demon King who is terrorizing villages. But before he goes, he can choose one item of any kind to aid him in his quest, and the future hero selects Aqua. But Kazuma has made a grave mistake—Aqua is completely useless! Unfortunately, their troubles don't end here; it turns out that living in such a world is far different from how it plays out in a game. Instead of going on a thrilling adventure, the duo must first work to pay for their living expenses. Indeed, their misfortunes have only just begun!

Novice bounty hunter Chateau Dankworth never expected to encounter someone capable of overpowering her in combat. Even less so that the mysterious man would take an immediate interest in her—to the point of aiding her missions. However, Chateau makes it clear that she has no plans of entertaining any personal involvement with him. Chateau's company is soon tasked with eliminating Song Ryang-ha—an expert assassin and a former member of a powerful Asian organization. Coincidentally, Ryang-ha is the man that has been pursuing her. Despite his background, Chateau reluctantly agrees to meet with Ryang-ha as part of a deal: in exchange for going out with him, he will provide her with the locations of current targets, dead or alive. But when the past begins to haunt both killers, their arrangement may need to come to an end, as their entanglement puts their lives at grave risk.

After fanatically playing the VRMMO World Fantasy Online for almost a year, the shut-in yet relatively affluent 15-year-old Yuna receives a bear costume from the game's administrators. The outfit, while somewhat embarrassing to wear, turns out to have overpowered stats and effects that make her character significantly more powerful. After accepting the bear equipment, she finds herself transported to another in-game world that prevents her from returning to reality. Confused and unable to log out, Yuna sets out to explore this new environment. She rescues a girl named Fina from wild wolves, who then guides her to the city of Crimonia. With her eccentric bear attire, however, Yuna stands out wherever she goes, and alongside her boosted fighting prowess, her reputation quickly rises—to the point that people give her the nickname Bloody Bear. Undeterred by this change in her life, Yuna decides to take on the role of an adventurer and fully enjoy herself in her new world.

The day is as normal as it can be in high school as the students peacefully go about their everyday activities until an unprecedented catastrophe strikes the school, killing every person in its wake. Guided by what seems to be a miracle, a handful of students are fortunate enough to be reincarnated into another world as nobles, princes, and other kinds of people with prestigious backgrounds. One girl, however, is not so lucky. Being reborn as a spider of the weakest kind, she immediately experiences the hardships of her dire situation. Even so, she must press on to survive the numerous threats that endanger her life. Discovering that her new world has a system like that of an RPG, she tries her best to hunt prey and defeat monsters to level up and evolve. As she gradually grows stronger, she hopes one day her efforts will be rewarded, and that she will be granted a better life.