Earth

The Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is in effect a ball of hot mud, but on the surface it's cold enough, so most of us live on it (or are supposed to). It is circa 4.5 billion years old, and, unless we humans succeed in destroying it over the next couple of centuries, it is expected to last for quite another while, though the changes in the Sun's emissions due to its aging will likely cause the extinction of everything; the species of earthlings are guaranteed to die, even if we fail to kill them -- unless, of course, we find ourselves another planet and figure out a way to take everything there. Our little planet on a corner of this galaxy may mean nothing in the grand scheme of things, but to its inhabitants it is their home, so, as a species, we cherish it dearly, to the point many cultures even to this day deify it. Being the home to the human civilizations, the Earth is the main setting of most fiction, be it anime or otherwise, but not only are many titles set in other places, such as unrelated fantasy worlds, in a considerable number of fictional titles the Earth is actually destroyed by aggressive alien invaders.