The World where Dungeons exist, an existence that has been a thing of mystery to the populace.
Sudden appearances can cause disturbance among the populace.
If a Dungeon has grown strong enough, it is capable of birthing even Demon Lords, Immortals, Dragons, Devils, etc.
The Populace has experienced such things in the past, resulting in dungeons becoming a mark to be destroyed before growing too powerful.
Now a new dungeon is born, housing a lost soul from Modern Earth.
How will this new sentient dungeon survive in this world?