Worlds and Universes

Introduction. The difference between the two.

Before I start explaining everything I would need you to forget whatever you know of the terms "world" and "universe". Yes the word is the same but the meaning is totally different. Read everything with an open mind. When I say "shadow" I don't mean the actual shadow that we all experience and have. To prevent confusion I would talk about the most popular species  as human. This has been explained like that to me as well so I don't want to change it.
Everything I know I have learned from someone who I shall explain later.

World- A personal alternative reality. The more we live, the more worlds we create. Every time you blink there is a world in which you did not blink this time. People cannot travel through worlds. The only way to do so if you die. You then move onto another world and continue on until you have lived a full life and die from old age. If you die from a serious illness like cancer, you will be send to a world where you did not yet have cancer and wont have it. That said if you commit suicide you will be send 2 hours later where your suicide attempt will fail, therefore sending you into darkness. 

Universe- Millions upon millions of them. Every one has different rules of existence. Closer universes are similar. Every universe is the way we know out Earth. We orbit around the sun, there are tons and tons of planets. A universe is not life on other planets. Our universe contains everything we can ever know. Be it aliens, monsters and so on. There are things impossible to learn, this is when our universe gets destroyed. When we have learnt everything. By destroyed I mean literally, no more life, no more planets, no more stars, nothing. Eternal nothingness. 

Shadow creature- A human whose universe got destroyed in unexplained way and cannot be brought together (this depends on the rules of existence of the universe as well) that, is almost always. The only time where no shadow creatures get created are if the universe deletes itself. Shadow creatures go into other universes and wait patiently for their chosen one to finish their life. Now both the shadow creature and the original share the body and mind. Up to 3 creatures can live in a body. In the impossible outcome that there are no more bodies a new universe is created.

Traveller- Someone who can easily commute between the universes.