MC found out that he is actually a reincarnator from Earth, in... Earth? Hold up... No. This world isn't Earth, like at all. Not even a parallel Earth!
Every children of this world need to learn at least one style of martial arts before reaching the age of 17. While the world looks very normal, even lacking in technology compared to Earth, it is anything but.
The moment a person reach the age of 17, they would be sent to roam the 'lower realm' called the Xenoverse. While reading some books in the home library of his adoptive, crouching tiger, parents, he found out several piece of informations that perfectly represent the world's position.
A massive world that is bigger than the whole Xenoverse. However, Edward the MC, felt that this world is no bigger than Earth. He wasn't wrong, but he wasn't right either.
Edward in fact, is no longer a human though he and everyone around him in this world looks like one. As a means of comparison, the size of a human compared to the current him, is no bigger than one tenth of an atom.
The world he's currently living in, has no definite name, but a few inhabitants of Xenoverse that knew, called this world, 'Dwelling of Unspoken Beings'.
As ominous as it sounds, it is the extent of what dwellers of Xenoverse knew about the world beyond the Xenoverse.
Universe ->Multiverse ->Omniverse ->
Metaverse ->Hyperverse->XenoVerse