The Omniverse is a single reality. It contains a single fraction of existence, or the existence itself.
About the Omniverse
The Omniverse holds everything that can be accessed through progressive powersets of any particular base universe (or "reality") within itself. Contains multiple different Omniverses. (Smaller). And the Marvel Omniverse looks different from all the rest as it is here as well. It sits around with the rest. The Absolute Creator Anthony, made multiple different Marvel Omniverses. The only trait every single thing within the Omniverses share is that it exists. How it exists varies in countless ways.
Beyond the Omniverses
The Omniverses exists in the surrounding emptiness known as The Outside, a void of virtual nothingness. Whatever may lie outside of these concepts is simply referred to as Beyond, one of the many iterations contained by Transcendentem.
Two Godverses orbit the Omniverse, one belonging to the Creator (God), and one to the Destroyer (Satan).
These verses can also cause paradoxes due to time travel to the past.