Knowing the location of 0, you started to connect the dots in your mind. Everything started to make sense now. Everything was planned brilliantly. -1 started the fight, not because it liked 0 but because it wanted to become the king. In the world of integers, it has been nobody just like number 1, but in the world of negative integers, it would become king, if and only if 0 was removed from the picture somehow. So, it constructed the wall with 0 inside it, without anybody knowing about it.....
The only way to show the truth is to break the wall. So you, along with your friend -13 and some others, break the wall at night. And there it is!!!!!! You found 0. The moment 0 came, the number line was restored to its proper order-
0 divides the two states of positive and negative integers. So, 0 lies in between the negative and positive integers.