Deca-Dence has elements of an isekai but it’s not really an isekai anime.

The roles are reversed where post apocalyptic Earth is treated as a fantasy world and cyborgs act as the players. However, Deca-Dence is still not technically an isekai as the cyborgs are not being transported or reborn and the setting is not really set in a fantasy world.

There is no one from Earth that is transported to, reborn or otherwise trapped in a parallel universe, fantasy world, or virtual world in Deca-Dence. Instead, Earth is used as a mere game for cyborgs who only join through supposedly safe avatars while humans are treated as NPCs (Non Playable Characters).

Is Deca-Dence a Virtual Reality Game?

The Deca-Dence universe also isn’t a virtual reality game.

It is treated as a game, or a entertainment facility by the cyborgs and the “Gears”. Humans are unaware that their lives and world is being treated as a game.

Through the eyes of the humans, the events that happen in Deca-Dence are real and traumatic.

Deca-Dence Setting

Deca-Dence takes place on Earth. However, huge levels of pollution turned the planet into an unlivable wasteland.

Huge mega-corporations saw this as an opportunity to seize further control by pumping out cyborgs that could survive in these harsh conditions. The rest of humanity were eventually purchased by the Solid Quake corporation.

The Solid Quake corporation decided to build a massive entertainment facility called Deca-Dence by creating a giant dome on the Eurasian continent, where they act as a governing body and make all the decisions.

 Cyborgs also enjoy an illusion of agency, as their entire existence belongs to a corporation they can never go against. Humans or a cyborg that goes against the system are labeled as a bug and eliminated.