Sky. The first thing the young man sees when he comes to another world is a deep blue sky. Without any notice, without any reason, suddenly, Watase Kousuke who had come to another world by accident, defeated a dragon, and in the process saved Horun, a noble girl who was about to be sacrificed. After the dragon-slaying incident, Kousuke's power suddenly increased, furthermore his potential also rapidly increased as he spent more time in that world. Kousuke, together with Horun went to the house of a witch called Eliciel, to learn more about this world. Kousuke with the acquired fundamental knowledge, has decided to go to a city called Berazen, to visit Horuns foster parent Bordos, and also to try to survive and live in this world. Kousuke will experience several meetings, across several accidents in his way to accomplish the ordeal.

Original Web Novel