Natsuki Subaru, an ordinary high school student, is on his way home from the convenience store when he finds himself transported to another world. As he's lost and confused in a new world where he doesn't even know left from right, the only person to reach out to him was a beautiful girl with silver hair. Determined to repay her somehow for saving him from his own despair, Subaru agrees to help the girl find something she's looking for.

Neku awakens in the middle of Shibuya's bustling Scramble Crossing with no memory of how he got there. Little does he know, he's been transported to an alternate plane of existence known as the Underground. Now an unwilling participant in the mysterious "Reapers' Game," Neku must partner up with a girl named Shiki in order to survive...

Japanese anime television series

A mysterious switch appeared one day. Upon pressing it, they were sent to a different alternative world!! There are also characters from other alternative worlds gathered together...!?

Tatsumiyajima is the central island in the middle of a small cluster of islands, in a sleepy backwater of the Japanese isles. Not much happens there, and the island's young people go to school knowing that their lives are likely to remain peaceful and undisturbed. Or so they have been taught...but the truth is different. The fate of mankind is on the line, and Tatsumiyajima is the last line of defense against a hostile and incomprehensible enemy. At the center of it all, fighting for Humanity's continued existence, is the giant robot Fafner, the dragon that guards this final treasure of mankind.

Misaka's electro-manipulation skills - and her delightfully destructive railgun projectile movement - make her a rock star in Academy City. The techno-metropolis is filled with supernaturally powerful students known as Espers, including Misaka's flirtatious friend and roommate, Shirai Kuroko. She uses her teleportation skills as a member of the Judgment law enforcement team, fighting crime alongside fellow agent Uiharu. Joined by their friend Saten, a spunky Level 0 Esper, Misaka, Kuroko, and Uiharu have a blast taking on danger whenever and wherever it arises.