Humanity had been considered Legends from a bygone ago and are now treated as myth, A world not to dissimilar to our own but it had gotten stale for the Gods that watch the world and decide to spice things up by bring humanity back in a very violent way.
Jackson was a normal Girl that had all ways been a tomboy, but not know to many outside of her small group of friends is that she has no regards to Human life, which is why when she join the Army she was found to creep out her drill instructors. And her disregard came to ahead when she ordered her men to rush a Enemy MG position and when the men she told to do it didn't she just killed them and said "A Waste of both my time and the Nations." But a few days later she would die in a "Friendly Fire" incident and that is when she was grabbed by the Gods and taken to their Earth.
And in this new world she was told one thing, "Do what ever you want." With those word she starts having fun.