[WARNING!!! This is a side story, you can read this if you want. But it will contain some major spoilers.]
After changes, most of the people adapted to that.
The aftermath of war can be a challenging time for people as they must adjust to the changes that have occurred in their lives. It is essential to move forward and not dwell in the past, as dwelling in the past can hinder progress and growth. The individuals who were affected by the war realized this and came up with a proactive solution.
Like most of the system changed.
As the people grew stronger and learned how to defend themselves against the monsters, a new profession was born - the Hunter.
This profession was also known by other names such as Adventurer or Bounty killer. With the increasing number of hunters, group activities like Guilds and Associations also began to emerge.