The sky. That was the first thing that the young man saw. The deep blue sky. “Without a warning or any reason I, Watase Kousuke, was thrown into another world. I killed a dragon and saved the noble girl Horun who was sent there as a sacrifice” After killing the dragon, his power greatly increased and he was granted the chance to live in a different world. Together with Horun, they went to the home of the Witch Alice to ask about this world. After learning about the events leading to Kousuke appearing in this world, they went to the city Berassen in order to test if he will be able to survive. This is his adventure.