You’re not alone. Whenever, forever.

Yuuta Hibiki is a first-year student in high school living in Tsutsujidai. One day, he wakes up without his memories. Yuuta later meets Hyper Agent GRIDMAN who is inside an old computer. GRIDMAN tells him to fulfill his purpose. Yuuta’s quest to understand the meaning behind those words and to find his memories begins. While all of this is sudden, Yuuta has helpful assistance from his classmates, Shou Utsumi, Rikka Takarada, and Akane Shinjou, but…

Those peaceful days are destroyed mercilessly by a monster that suddenly appears.

Asahi’s life in reality ended simultaneously when she died playing Union, a world-renowned online RPG. The members of Subaru went separate ways when Union shut down due to Asahi’s death. Six years later, Haruto logs onto a renewed version of Re’Union and reunites with Asahi who had died. Is it really her or just an electronic ghost? The former team members reunite and enter the mysterious and deadly online game to find out.

Kuroi Souya is a high schooler living a peaceful life despite having no memories of his past. One day, however, his town is attacked by one of the mysterious Nebula Weapons. Together with the cat-like “Sensei” and the gothic lolita Ginko, Souya gets dragged into a battle against… seven superheroes who protect the town! What is Souya’s reason to fight? The answer lies in his memories.

After unknowingly participating in a kidnapping, college student Yuuya Nomoto finds his friends brutally murdered by Hitomi Uzaki, the high school girl they attempted to abduct. Forced to drive her to an undisclosed location, he finds himself being wagered as the prize for a death match between two Therianthropes, superpowered human-animal hybrids created through advanced gene therapy. As one of these hybrids, Hitomi uses the speed and fearlessness she gained from her ratel genes to viciously dispatch her foe and save Yuuya from certain death.

Waking up hours later hoping the whole event was only a nightmare, Yuuya realizes that he has become embroiled in a secret proxy war between four large Japanese business conglomerates, with the winner taking control of the economy. As her sole albeit unwilling investor, his life is now directly linked to Hitomi’s ability to participate in underground bloodsport matches known only as Killing Bites.

The Abyss—a gaping chasm stretching down into the depths of the earth, filled with mysterious creatures and relics from a time long past. How did it come to be? What lies at the bottom? Countless brave individuals, known as Divers, have sought to solve these mysteries of the Abyss, fearlessly descending into its darkest realms. The best and bravest of the Divers, the White Whistles, are hailed as legends by those who remain on the surface.

Riko, daughter of the missing White Whistle Lyza the Annihilator, aspires to become like her mother and explore the furthest reaches of the Abyss. However, just a novice Red Whistle herself, she is only permitted to roam its most upper layer. Even so, Riko has a chance encounter with a mysterious robot with the appearance of an ordinary young boy. She comes to name him Reg, and he has no recollection of the events preceding his discovery. Certain that the technology to create Reg must come from deep within the Abyss, the two decide to venture forth into the chasm to recover his memories and see the bottom of the great pit with their own eyes. However, they know not of the harsh reality that is the true existence of the Abyss.