Draw the Sword Billions of Times

This is a world where demons and humans coexist. Demons are rampant. Humans do not want to have any contact with demons, but in a border town, a young man kills demons every night. In fact, he was disgusted deep down, but in order to complete the task of drawing the sword hundreds of millions of times. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.