My name is Niche.

I am an immortal, but not the kind you know of.

I can die, I have died.

I am not invincible or highly resistant to hazards. In fact, I'm as easily hurt as the rest of you.

I am immortal because of my pestilent soul. I die, but the moment I come in contact with a living organism, I become a part of it. I am it.

I have taken over its life.

There is no more "it."

I've become so good at becoming it, that its friends don't notice it is gone.

When I die as it, I simply move on.

I find another it.

Its are everywhere, they're limitless.

Its that are connected all fall under my control, and those are the ones I've had the most fun in.

And when all its are connected and I've come out on top...

There is only me, Niche.