Aransae - The Main Character is exiled from his world by the God for becoming a Menace. He finds himself in a new world, having forgotten all his memories and who he was. The only thought surrounded by destructive desires.
He takes over a building, and divides his energy into 33 Floors. Each holding a monster filled with desires of humans, their obsession.
Despite having forgotten who he was, he choses to consume and purify these desires through lust rather than destruction and killing.
Rias and her Peerage, carrying the responsibility to curb any stray demons in Kuoh Town enters the Dungeon to figure out its origin only to fall at the hands of monsters one after the other.
Aransae, hoping to find a physical body makes a contract with the male members of Rias's peerage to borrow their body.
In due time, he makes a body of his own and gives up the control of the Dungeon.
The Dungeon, now not controlled by him, starts to go out of control.
Aransae realises that his memories are a part of the Dungeon, since the Dungeon is him.
He starts clearing the floor to regain his authority and memories.
After clearing the first floor, he regains a memory and authority of the first floor.
With newfound powers, he tries to create a monster in the shape of his two friends from the memory.
For reasons he couldn't understand, they wake up with their ego and all their memories. But for some reason they choose to stay dead and reincarnate in another universe.
The Dungeon, mostly not in control of Aransae, uses his Conceptual Power to connect itself to other worlds and devour the desires of the humans and grow.
Aransae visits one of the worlds, where his friends have reincarnated, to play the role of the villain.
But the Dungeon energy mutates the zombie virus in the world, causing humans to experience genetic changes when they grow past a certain level.
Not knowing what it would do, his friend races to grow stronger, only to become a vampire.
He refuses to play Aransae's game any longer and asks him to send him to a world where he could use these newfound powers.
One day, Aransae visits his friend in the Third World (Naruto) only to hear his desire to kill himself.
Aurum divides his Mind (Aurelius), Body (Arcus), Soul (Aurum - To be Born)
Having lost a friend, Aransae's desire to know about himself becomes greater. He choses to take Rias and his others friends to Fourth World (SAO) where they could spend a few years in VR, grow stronger and he could have the time to find himself.