Multiverse

The Multiverse is the total accumulation of all forms of space, time, matter, and even energy. It serves as the container for all subsequent realms or universes, each with their own unique characteristics, traits, and law of physics. Given it's status as the vessel of all form of matter - non-corporeal or physical - it serves to reason that the Multiverse is also primordial, having existed before the history of existence as we know it.

Overview
The concept of a multiverse is still something that is relatively unknown to mortal-kind. While it is certain that there are other planes of existence, particularly with the recent events of Yōkai emerging, it still remains unknown just how many different dimensions exist. In addition, the means to entering specific planes of existence also is an unknown variable to the world at large.

History
The history of the Multiverse is still unknown. However, there is no evidence that anyone has ever come to threaten or even rule the entirety of existence.

Energy Consumption
The Multiverse serves as the connection between all form of existences, as it essentially weaves and knots together every form of space in some shape or form. However, to travel from one Realm to the next often requires an absurd amount of energy, typically making this a futile endeavor for most organisms. Nonetheless, if able to conjure up the necessary power, or if the natural balance has been torn enough to cause for spatial rifts, or breaches, then a person can readily travel to a different form of space.

This, sadly, doesn't guarantee that you'll be able to travel to where you want.

In addition to this factor, while all dimensions or realms are encompassed by the multiverse, some are closer to than others, making the difficulty a wild variable. In addition, the conditions of the realm itself can also modify or alter the degree of difficulty, for example traveling from Makai to the Human Realm, is a far easier endeavor that the opposite scenario.

Limitations
In addition, it is easier to send non-living objects through space and time than it is to send the living. Adding onto this, if the recipient of a teleportation method is powerful, most notably in chakra, they too will find it more difficult to travel over.

Pocket Dimensions
Pocket Dimensions

Along with the existence of universe, the multiverse also contains Pocket Dimensions. Pocket Dimensions are often internal planes of existence contained within a universe, and thus it only becomes accessible while the individual is in the parent domain.

Human Realm
Human Realm

The Human Realm is the universe in the Tales of Forgotten series takes place. It's the home of the most prominent race, the Humans, and serves as an area ripe with bloodshed and chaos. Some astrologist, those who study the concept of space and the multiverse itself, the Human Realm may be at the center of the multiverse, making it an area of interest.

Makai
Makai

Makai is the world from which the Yōkai originate from. The realm is said to be filled to the brim with all types of demonic foes, with some even being rumored to have been the basis for various, common religion among the human realm. Makai remains one of the more prominent dimensions in all of the multiverse, constantly meddling with the affairs of others.

Avalon
Avalon

The anti-thesis to the Demon World. Avalon is said to be the home the divine Tenshi, a race of angelic beings that preside in a higher realm. Avalon directly neighbors Makai, bringing the two into constant conflict given their fundamental and ideological differences. Unlike their demonic cousins, the Tenshi prefer not to directly meddle with affairs of other dimensions, opting to provide aid indirectly to evade disrupting any potential balance.

Pure Lands

Pure Lands

The Pure Lands is an after life dimension, made solely for individuals who have died with good karma, or lack of taint. It serves as a blissful, eternal plane where the fallen may meet up with their lost ones, and life-long enemies may at last be able to set aside their differences. The Pure Lands isn't a known phenomenon to the general public.

Gehenna
Gehenna

Gehenna serve as the direct opposite of the Pure Lands. It's a dimension of the wicked, where those who were corrupted or evil at eventually sent upon their death and judgement. Gehenna holds a reputation as an area of unimaginable suffering, no matter your persona or tastes.

Limbo
Limbo

Limbo is an invisible realm that co-exists with the physical realm, while also serving as the location of a soul's official judgement. It is possible for a spirit from the Naraka plane to arrive here undetected and eventually interact with the physical world.

Naraka
Naraka

To arrive in the afterlife, the souls of the deceased has to tranverse through a middle-plane, connecting them to either of their eventual destinations. This plane is called Naraka, otherwise known as Purgatory. Some souls find themselves unable to let go, and become trapped - either intentionally or by accident.

To arrive at this place, the deceased has to go through a middle plane of existence, wher