Ambiguous immersive online game, it has the Yamaguchi Mountain setting, there are dungeons, there are main quests, there are hidden professions... The background of the game is "Falling Moon".
In short, this is the story of a thief who ran rampant in the online game world. He disappeared for ten months and then returned to continue his rampage. However, the person who came back was no longer a "human"...