Reality

Reality, also referred to as the Human World, is the world made of physical matter where humans reside.

Overview

The world of Oneirosea is an alternate near-future version of the real world, with the point of divergence being the existence of mist. Most of the planet's geography, languages, and cultures are close equivalents to those in real life, with slight changes.

Reality is made of physical matter, which is the generator and antithesis of mist. Things composed of mist, such as dreams and demons, cannot survive in reality unless they are protected by a body, as they will be overwhelmed and destroyed by matter. However, reality's dominance over dreams is not absolute, and it is possible for the balance to shift. If the total volume of human dreams were to become larger than reality, or a huge amount of mist were to be brought into reality at once, it is possible that mist would start eating away at matter instead.

Reality is paralleled by oneirosea, a dimension born from human dreams.

Culture

Most holidays, religious beliefs, social norms, etc. in the series' reality are very similar to those from real life. However, since humans have known about the existence of oneirosea for thousand of years, this has caused some divergences.

Population

The population of humans appears to be much higher than that of the real world. Nanami Murakami refers to the town she moved to as small and rural, but it is still depicted with tall apartment buildings and vertical farms. Despite this increase, people are more physically isolated from each other than they were in the past. Virtual events are more common and popular than physical ones, and most people rely on drone delivery rather than physically visiting stores.

There are some hints that this overpopulation has caused environmental disasters and resource shortages. In particular, most meat shown in the series is artificial, while real red meat is considered fancy and expensive.

Religion

Religion and gods are rarely directly discussed in the series, and few characters are devoutly religious. However, judging by the presence of Shinto shrines and religious holidays such as Christmas, it can be inferred that most real-life religions exist in this world. These depictions are generally highly commercialized, focusing on merchandise and profit rather than their spiritual origins.

Original myths about oneirosea are also present, and sometimes interwoven with real-life religions. In particular, oneirosea seems to be conflated with hell or the afterlife in many religions. Depictions of hell within the series are usually dark, cold, and watery, similar to the deeper zones of oneirosea. There are even cults who believe that oneirosea is literally an afterlife, and/or that demons are former human souls receiving their punishment. Some of these cults are harmless, but others perform ritual killings during astral projection in order to guarantee their entry into the afterlife. Alcyon Corporation sometimes airs informational programs debunking these beliefs for the sake of public safety.

In some places, All Hallows' Eve is considered to be the time when the barrier between reality and oneirosea is the weakest. In order to avoid being possessed, people hold parties where they tell ghost stories and stay awake until dawn breaks.

Technology

Science and technology in Oneirosea's reality is more advanced than the real world. Brain-operated cybernetic limbs, advanced medical technology, and minor biological modifications are all considered unremarkable in large cities such as Semikawa. Since real-life modern technologies such as VR headsets also exist, and are occasionally referred to as outdated, it seems that these advancements are simply due to the passage of time.

There is a particular focus on hologram technology within the series. Hologram projectors can create translucent images or animations and detect when matter passes through them, allowing them to serve a similar purpose to touch screens. Small, compact ones projectors are widely available to the general public, and are integrated into cell phones, cybernetics, fashion accessories, and so forth. Larger and more complex projectors are used to create billboards, art installations, and virtual reality environments.

There is also a unique branch of science in this universe that focuses on the study of mist and dreams, usually referred to as oneiric research (in order to distinguish it from the real life science of oneirology, which is more focused on the functions of the brain). Technology developed from this branch of science can be used to awaken supernatural powers, travel to and from oneirosea, and view the contents of dreams to a certain extent. Alcyon Corporation and Labyrinth are two frontrunners in the field of oneiric research, and are constantly developing new technologies using mist.

Locations

The events of the series mostly take place in a few fictional Japanese cities, but real-life locations such as Aomori Prefecture and Silicon Valley have also been mentioned.

Semikawa City

Main Article: Semikawa City

Semikawa is the city in which most of the series takes place. It is the hometown of Hiro Nimura and the site of the Alcyon Corporation headquarters building.

Aobashi City

Main Article: Aobashi City

Aobashi City is a resort town not far from Semikawa, mostly featured in omakes and bonus materials.