The Hunter and The Hunted

The Hunter does not know his targets face, but he knows that while his target is alive, he cannot exist. The target must be eliminated, and quickly.
The Hunted is oblivious. But there is obviously something very, very wrong. He knows that his life is at stake if he doesn't find out what.
There is not enough room in this world for the both of them, their sole purpose is to survive by all means necessary, even if it means turning against yourself.

This is an original short story.