Box in the Empty

There were once two siblings in a box, somewhere in the Empty. 

The Sister was powerless in her wake, her abilities only active during her sleep. The Brother, however, kept the Eternity of the Empty in check, always awake; for if he ever slept, time would surely stop. The siblings were the brain and heart of the very Empty itself.

They had been there for a long time, gazing at what would have seemed like stars outside. Tired of her powerless existence and the nothing around, the Sister decided to sleep.

“Brother, I am going to dream about the world.”

Leaving her brother behind, the Sister went into a deep slumber, and dreamed about many things.

She dreamed about a world where spirits and creatures of many different kinds could exist. A place for her and her brother. Her favorite.
She dreamed about a world with humans in a floating orb of stone, people who looked like the siblings, but would never have to be confined into a box for eternity.
She dreamed about a world where humans and many other creatures could connect with the essence of nature through magic.
She dreamed about a world where only a few had special powers, a mix between the previous two; and the conflicts that would arise.

And lastly, she dreamed about a world for her brother. A world with a bit of everything.

Filled with curiosity, the Brother visited all the worlds. He took on countless forms and identities, enjoyed many adventures, observed those who were living their own. His sister had filled the Empty with the many possibilities one can only dream of.

But slowly, he came to notice that no one would ever know the face of their creator. Her voice. Her name.

“Sister, are you watching?

I have seen the world you've made for me. I've given them power, watched over them, seen them mess up and become strong. I've seen them create amazing artifacts. I've visited all your worlds. The land of your dreams is an incredible place.

But what is the point if you can't come along?”

Then, the Brother realized.

That should his sister ever wake,

that would surely be the end of the world.