The world was dying, there was little left in the way of thriving vegetation and animal life, clean water was a shore to find, and bit by bit the people that had survived the incident were dying off like the planet. Maverick has been on her own since the age of twelve when the last of her family passed. To keep herself safe (and out of the hands of those that would… not treat her well) she left the village and the last remains her her tribe behind. She travels with a massive F1 Savannah that she managed to save the life of. Now, Ash follows her around in much the same manner as a puppy might. He hunts with her, sleeps by her side, and protects her very life.
It should be noted that, while Mav appears to be elven, she is in fact a human that has mutated.