17 year old, Nero Toujo is transferred into a new world after finding out him and his younger sister, Masuki, have immense powers. Brought to this world, they find that living in it isn't so bad and not that different from living in Japan. But, upon this arrival to the new world, an enemy from within is lurking and looking for the chance to take out the pair of siblings. They strive to be the best of the best with help from a guardian angel named Karin, but will it all be enough. Is Nero strong enough to protect his sister and all of his new friends in this new and crazy world?