According to legend the universe was created by the only omnipotent being ever to exist who woke up and in the first seconds of his consciousness created the universe as we know it before destroying himself in fear that no one should wield this absolute power, not even himself. It is believed that the remnants of his destruction formed into the mana veins and magic throughout all universes.
While much is unknown about the universe and no one has ever mapped it, or has a full understanding of what it is composed of, over years certain realms of space and time have been established.
The Overworld is the world as we know it, home to the ten species and all the history of Crecia leading back to the beginning of time.
Midworlds are the names given to the pillars of magic throughout the Outworld that connect the realms together. Some midworlds are stronger than other, but regardless they make travel between realms possible.
There are particularly strong midworlds between the Everglow and Overworld, allowing demons to cross over and inhabit it.
The Everglow is an ever changing realm of chaos and discord, where magic flows freely throughout causing space and time to work ways unimaginable in the Overworld. It is un-mappable and built from pure magic and as such has very different laws that bind it together. The Everglow is the home to demons.
The Everglow is the only other realm known of other than the Overworld. It is estimated to be rather close in proximity to the Overworld due to their close relations.
Everything lies in the outworld, a void of space in which other realms exist and can be accessed via midworlds, pillars of magic that connect the realms together. Only one other realm is known to Crecians, however, the Everglow.
The Outworld is not a realm, so much as the void of space in which many realms lie. Few known beings are able to traverse the Outworld but those who can are usually very powerful.