Boy. I went round and round on this. When I finally got away from möbius thoughts, I remembered how your riddles go. This may not be right, but...
The letter "e?" I had to combine "Every single placE," so I may not have it.
A riddle! I am something.I am the beginning of the end. I am the end of time and space.I am extremely essential to creation and I surround every single place. What am I?