It is the Taisho Period in Japan. Tanjiro, a kindhearted boy who sells charcoal for a living, finds his family slaughtered by a demon. To make matters worse, his younger sister Nezuko, the sole survivor, has been transformed into a demon herself. Though devastated by this grim reality, Tanjiro resolves to become a "demon slayer" so that he can turn his sister back into a human, and kill the demon that massacred his family. A sorrowful tale of siblings in which the fates of humans and demons intertwine... begins now!

“Where...am I...?” Before he knows it, Kirito has made a full dive into an epic, fantasy-like virtual world. With only a murky recollection of what happened right before he logged in, he starts to wander around, searching for clues. He comes upon an enormous, pitch-dark tree (the Gigas Cedar), where he encounters a boy. “My name is Eugeo. Nice to meet you, Kirito.” Although he is supposedly a resident of the virtual world - an NPC - the boy shows the same array of emotions as any human being. As Kirito bonds with Eugeo, he searches for a way to log out of this world. Meanwhile, he remembers a certain memory deep down within him. He remembers racing through the mountains with Eugeo as a child… A memory that he should not have in the first place. And in this memory, he sees someone other than Eugeo, a young blond girl. Her name is Alice. And it is a name that must never be forgotten...

In the near future, a Virtual Reality Massive Multiplayer Online Role-Playing Game (VRMMORPG) called Sword Art Online has been released where players control their avatars with their bodies using a piece of technology called: Nerve Gear. One day, players discover they cannot log out, as the game creator is holding them captive unless they reach the 100th floor of the game's tower and defeat the final boss. However, if they die in the game, they die in real life. Their struggle for survival starts now...

Assiah, the realm of humans, and Gehenna, the realm of demons. Normally, these two dimensions would never intersect, but having possessed all material substances, the demons are now intruding on the material world. But among the human race, there are those who can confront such demons - the Exorcists. Born the spawn of Satan, Rin Okumura decides to hide his origins, and become an exorcist. He enrolls at the Exorcism Cram School, a training institute for exorcists located on the True Cross Academy grounds. But, his cover is blown during an attack by Amaimon, the King of Earth, and he is revealed to be the son of Satan. Terrified of Satan’s blue flames, his friends start to distance themselves from Rin… It is then that someone steals the Left Eye of the Impure King, sealed away in the deepest part of the academy, and Rin and the others find themselves embroiled in an unexpected crisis…

Invertia (meteor storm)… an unprecedented disaster that struck the world during the 20th century. Because of this disaster, numerous cities around the world were destroyed. However, within the meteor, an unknown element called mana (all-encompassing element), was discovered, which allowed human technology to make rapid strides, and gave rise to a new species of human born with unique skills – the Star Pulse Generation (Genestella). The setting for the world’s greatest all-around battle entertainment, the Festas (Star Warrior Festivals), is an academy city above the water surrounded by six academies called Rikka, also commonly known as Asterisk. Having transferred into Seidoukan Academy in order to fulfill his own wish, scholarship student Ayato Amagiri swears to himself that he’ll fight in this city. Burning souls race… The curtain rises on school battle entertainment!