In de nabije toekomst botst de aarde met een gigantische meteoriet. Al het levende organismen, inclusief de mensheid, wordt hierbij van het aardoppervlak weggevaagd. De overheid, die deze uitkomst had voorzien, was al met voorzorgsmaatregelen bezig. Project 7SEEDS; hiervoor werden vijf teams van zeven jonge gezonde mensen ingevroren, zodat ze deze tragedie konden overleven. Samen moeten ze nu zien te overleven op een Aarde die niet meer is zoals hij was.

While fighting an intense inter-galactic war, a mecha pilot is accidentally warped into a space-time neither he nor his computer recognize. After waking up from a long-time hibernation, he finds himself trapped on a planet, with human residents talking in an unknown form of language, using inferior technologies, and - most shocking to him - naturally breathable air.

Ganta is the only survivor after a mysterious man in red slaughters a classroom full of teenagers. He's framed for the carnage, sentenced to die, and locked away in the most twisted prison ever built: Deadman Wonderland. And then it gets worse.

'Objects' zijn krachtige, enorme wapens die de loop van oorlogsvoering veranderen en worden bemand door Elite Object-piloten. Een vreemd Elite-meisje genaamd Milinda ontmoet Quenser, een student die Object-monteur wil worden, met de soldaat-in-opleiding Heivia op een besneeuwd slagveld.

Sakamoto, an unemployed young man, is one of the world's top players of an online fighting game called Btooom! One day, he wakes up on what appears to be a tropical island, although he doesn't remember how or why he got there.

Fear, survival, instinct. Thrown into a foreign land with nothing but hazy memories and the knowledge of their name, they can feel only these three emotions resonating deep within their souls. A group of strangers is given no other choice than to accept the only paying job in this game-like world—the role of a soldier in the Reserve Army—and eliminate anything that threatens the peace in their new world, Grimgar.

When all of the stronger candidates join together, those left behind must create a party together to survive: Manato, a charismatic leader and priest; Haruhiro, a nervous thief; Yume, a cheerful hunter; Shihoru, a shy mage; Mogzo, a kind warrior; and Ranta, a rowdy dark knight. Despite its resemblance to one, this is no game—there are no redos or respawns; it is kill or be killed.

It is now up to this ragtag group of unlikely fighters to survive together in a world where life and death are separated only by a fine line.