You are a human male/female who's been transported to a relatively new world. This new world doesn't have a name, any specific species of animals, and certainly isn't abundant with life yet. This is where you come it, and you unwillingly have to help populate the world with another animal/being. You can pick any animal from reality, mythology, or just make up your own.
Just that you are the only human, and that there is a small number of a specific gender to breed with. Now the rules are basically this:
1. All transformations are accepted, no matter what.
2. NO, same gender sex, for the goal is to populate the world
3. You can transgender into any gender you wish, I never said it had to specifically be sex between a male and female creature.
4.NO COPY PASTING CHAPTERS!!!
That is all, now what is your gender