At the renowned Shuchiin Academy, Miyuki Shirogane and Kaguya Shinomiya are the student body's top representatives. Ranked the top student in the nation and respected by peers and mentors alike, Miyuki serves as the student council president. Alongside him, the vice president Kaguya—eldest daughter of the wealthy Shinomiya family—excels in every field imaginable. They are the envy of the entire student body, regarded as the perfect couple.

When Keyaru acquired his powers as a Hero who specialized in healing all injuries regardless of severity, it seemed that he would walk the path to a great future. But what awaited him instead was great agony; he was subjected to years of seemingly endless hellish torture and abuse. Keyaru's healing skills allowed him to secretly collect the memories and abilities of those he treated, gradually making him stronger than anyone else. But by the time he reached his full potential, it was far too late—he had already lost everything.

Deep in the forest, far from any human contact, there lives a child named Ryouma Takebayashi. He engages in the rather strange hobby of keeping various types of slimes as pets. Furthermore, despite his young age, he has a sturdy physique and good compatibility for magic. All of this is because, having endured much hardship in his previous life, three gods grace Ryouma with a second chance to pursue one goal: savor the wonders of life.

Dressed in a conspicuous outfit and armed with an eccentric spirit, Hina Satou goes around insisting that she is the Asgardian god "Odin." When she crosses paths with a boy named Youta Narukami, she uses her precognition abilities to warn him about an impending catastrophe threatening the end of the world. But being a teenager preoccupied with his problems, Youta finds it hard to believe such a preposterous claim.

Dressed in a conspicuous outfit and armed with an eccentric spirit, Hina Satou goes around insisting that she is the Asgardian god "Odin." When she crosses paths with a boy named Youta Narukami, she uses her precognition abilities to warn him about an impending catastrophe threatening the end of the world. But being a teenager preoccupied with his problems, Youta finds it hard to believe such a preposterous claim.

In the kingdom of Earlshide, Merlin Walford was once regarded as a national hero, hailed for both his power and achievements. Preferring a quiet life however, he secludes himself deep in the rural woods, dedicating his time to raising an orphan that he saved. This orphan is Shin, a normal salaryman in modern-day Japan who was reincarnated into Merlin's world while still retaining his past memories. As the years pass, Shin displays unparalleled talent in both magic casting and martial arts, much to Merlin's constant amazement.

Ever since the death of his father, the burden of supporting the family has fallen upon Tanjirou Kamado's shoulders. Though living impoverished on a remote mountain, the Kamado family are able to enjoy a relatively peaceful and happy life. One day, Tanjirou decides to go down to the local village to make a little money selling charcoal. On his way back, night falls, forcing Tanjirou to take shelter in the house of a strange man, who warns him of the existence of flesh-eating demons that lurk in the woods at night.

After a string of mysterious disappearances begin to plague a train, the Demon Slayer Corps' multiple attempts to remedy the problem prove fruitless. To prevent further casualties, the flame pillar, Kyoujurou Rengoku, takes it upon himself to eliminate the threat. Accompanying him are some of the Corps' most promising new blood: Tanjirou Kamado, Zenitsu Agatsuma, and Inosuke Hashibira, who all hope to witness the fiery feats of this model demon slayer firsthand.

Since ancient times, rumors have abounded of man-eating Demons lurking in the woods. Because of this, the local townsfolk never venture outside at night. Legend has it that a Demon Slayer also roams the night, hunting down these bloodthirsty Demons. For young Tanjiro Kamado, these rumors will soon to become his harsh reality. Ever since the death of his father, Tanjiro has taken it upon himself to support his family. Although their lives may be hardened by tragedy, they've found happiness. But that ephemeral warmth is shattered one day when Tanjiro finds his family slaughtered and the lone survivor, his sister Nezuko Kamado, turned into a Demon. To his surprise, however, Nezuko still shows signs of human emotion and thought. Thus begins Tanjiro's journey to seek out the Demon who killed their family and turn his sister human again.

The Hashira Training conducted by the Hashira is a special training session that aims to improve all Demon Slayers' abilities and physical health. The training is split between the Hashiras. First, the Sound Hashira, Uzui Tengen conducts training on basic stamina. Then, the Love Hashira, Kanroji Mitsuri handles flexibility training and the Mist Hashira, Muichirou Tokito, deals with the quick movement training.

Tanjiro, Zenitsu, and Inosuke go on their first mission together and venture to Mount Natagumo.

Too afraid to go up the "spooky mountain" with Tanjiro and Inosuke, Zenitsu stays behind. Tanjiro and Inosuke encounter a mountain laced with spider webs and controlled by Spider Demons. These Demons have already dispatched countless Demon Slayers, forcing Kagaya to send in the Hashira as reinforcements.

After fanatically playing the VRMMO World Fantasy Online for almost a year, the shut-in yet relatively affluent fifteen-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.

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.

In an unexpected turn of events, dull high school student Hiro Yuuki obtains the full dive role-playing game Kiwame Quest. Created by the best of technology, the game claims to take "reality to its extremes," from stunning graphics, NPCs' behavior, to the scent of vegetation, and even the sensation of wind brushing against the skin—everything was the result of an ultimate workmanship.