Run.

I've been given many names over my years of living. Most dominantly 'freak' or 'abomination', either one works I suppose. But what do you call someone that cannot die? Someone who moves faster than a speeding bullet or who happens to be stronger than anything else on the planet? 'Freak' sounds very justified now, doesn't it?
My name is Alexis, though my last name differs everywhere I decide to travel. Currently, I'm in New York and my last name is Williams, very common and wouldn't arouse suspicion.
I've been hunted for more than five centuries but those hunters could never really hurt me. Not in the way they wanted to. They've killed my family, my friends, anybody I decide to let near me. They were experienced assassins.
So I ran. I didn't allow anyone near me, I kept to myself. But I ran. I've been to just about every inch of the world and still couldn't find a place to settle down.
Until I met her. Mia Sanchez. The girl was a walking chew toy for the hunters, but she was persistent and located my soft spot. She was immortal in her own aspect, but nowhere near invincible when thinking of the skills the hunters harbour.
So I'm stuck protecting her and those around her, all the while hoping that the hunter don't somehow find a way to finally bring an end to me.
You thought your life sucked? Try falling for someone you could break in a split second. And that's how it is, I am an abomination stuck with another abomination acting as her own, self-employed bodyguard.