Sakamoto Ryota is an unemployed 22 year old who lives with his mother and spends his days doing nothing but playing video games. In the real world, there may be nothing special about him, but online, he's one of the world's top players of the combat game called Btooom. One day, he awakes on what appears to be a tropical island, though he has no memory of how he got there or why. While exploring the island, Ryota runs into a mysterious being who attacks him by throwing a strange looking bomb at him. Ryota then realizes that both his life is in danger, and that he has somehow become trapped in a real-life version of his favorite game. Ryota and the other "players" must now survive through the nightmare to figure out the reason why they ended up in the game in the first place.
Narumi Fujishima is an ordinary high school boy who remains isolated from his fellow classmates. One afternoon fellow classmate Ayaka Shinozaki invites Narumi to join the gardening club and introduces him to a reclusive detective named Alice. Alice hires Narumi as an assistant and puts him to work solving the strange mysteries of Angel fix, an illegal drug. Little does he know it could put him and Ayaka in serious trouble.
Genius gamer siblings (plus being NEET & hikikomori) Sora and Shiro are known as the undefeatable “__” (blank). Their talents and skills are so good they are considered as urban legend. One day, a young boy named Teto appears before them, claiming to be the “God” of another dimension where Sora and Shiro are summoned to, in which no violence is allowed and everything is decided by a game. Of the 16 different races residing in this world, “Humanity” is the weakest. After having the vast majority of their lands captured by the other races and being driven to the brink of extinction, Sora and Shiro challenge these one-of-a-kind battles of the intellectual powers in order to save Humanity.