Ryuugoroshi no Sugosu Hibi

Ryuugoroshi no Sugosu Hibi (竜殺しの過ごす日々) is a light novel series by Tona Akayuki with illustrations by Foo Midori.

Plot
The sky. That was the first thing that the young man saw. The deep blue sky.

“Without a warning or any reason I, Watase Kouske, 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 Kouske 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.