The Player that can't Level Up

Story:

Kim GiGyu awakened as a player at the age of 18. He thought his life was on the track to success, climbing 'the tower' and closing 'the gates'… But even after clearing the tutorial, he was level 1. He killed a goblin a day, and he was still level 1. Even after 5 years, he was still level 1. "Who would have thought that this kind of player would exist." No one knew.