“What do you mean” Lu Yun wasnt quite following Qing Yus line of thought. First she spoke of a third realm, now it was suddenly the fourth realm
“Take a look at this.” Qing Yu rose and stretched out a finger, drawing four concentric circles in the air. Each successive circle enveloped the previous one, but they were connected at the very bottom with the one starting point in common between all of them.
“The innermost circle is our realm. It continually grows and will one day assimilate the second circle—the chaos. This new combined realm will continue to expand and one day subsume the third realm, then the fourth, becoming a world without end or boundaries.
“As for how big the fourth realm is… I dont know that either. Maybe theres no border that defines its reach.”
She looked around at where they stood. It was bereft of anything other than the Bridge of Forgetfulness. Even the immortal dao couldnt extend into this place.
“The bridge has obtained a special power here thats helped it come alive and become a real life form…” Qing Yu frowned.
“Then what about those corpseflies on it” Lu Yun was beginning to wrap his mind around the situation. The fourth realm was an incomparably sophisticated plane of existence. Their own realm was inferior to it before it finished swallowing the chaos and that unknown third realm.
The Bridge of Forgetfulness had come alive in the fourth realm and the endless gigantic corpseflies on it set him very ill at ease. This fourth realm appeared quite empty, but there must be some sort of horrific existence living within it—unknown zombies, for instance.
Since Qing Yu had identified it as alive and not a zombie, there was no way these corpseflies came from it.
“I dont know…” Qing Yu shook her head. “I cant calculate any further. Theres no immortal dao here or the energy of our realm. Its so much less real than the chaos and its all I can do to deduce this much.”
“A few hundred billion, is it Lets go take a look!” With a wave of Lu Yuns hand, the Tome of Life and Death turned into a curtain of light that encased him and Qing Yu.
He didnt dare separate from his beloved in this place and the book was his only surefire trump card. He couldnt even sense the Gates of the Abyss anymore. If he wanted to return to the world of immortals or hell, hed have to do so through the Tome of Life and Death.
“Big brother, big sister, dont go over there.” The ethereal voice of a child sounded by their eyes. Startled, the couple halted in their tracks and looked backward at the same time.
A little girl wearing a red dress had appeared at some point and was standing charmingly behind them. She looked about eight years old, but also seemed to be not fully present on the scene. She was standing there, but also not there.
“That stone bridge has become a scary monster and itll eat you if you go over there. Youll turn into something like those flies,” she said earnestly.
“And who are you” Lu Yun asked the girl. “Why are you here”
“Me” A lost look flashed across her face. “I dont know who I am either… Im not here. Im in the world below.”
“The world below The third realm” Qing Yu asked subconsciously.
“So thats called the third realm…” The little girl nodded. “That used to be a battlefield where a lot of people died, and then someone tried to bring them all back to life. But that person failed, so they all turned into little flowers planted in that world.
“Im in that place you call the third realm to protect those flowers.”
“Little flowers Flowers like this one” Lu Yun pushed his hand forward, displaying a Hell Flower on top of it.
The little girl shook her head gently. “This kind of flower.”
A small flower of six colors appeared in front of her. It possessed six petals and three leaves, each of which seemed to embody a certain utmost rule and law, coming together to depict some sort of monumental truth.
Lu Yun and Qing Yu were instantly captivated by the hexacolored flower.
“Alright, I should be getting back. Many things in the third realm want the flowers for themselves, so I need to keep them safe. You mustnt go to the bridge no matter what. Itll eat you!” The little girl slowly faded away alongside her flower.
“Shes the manifestation of a treasure,” Qing Yu suddenly said. “A supremely powerful treasure so many times greater than Worldcarver, Heavenfall, and your Quietus.”
“A treasure” Lu Yun subconsciously thought of the relationship of the blood demon and Situ Zhong with their treasures.
“Shes not the treasure itself, but the manifestation of one. Shes not alive!” corrected Qing Yu. “I wonder what level of existence it takes to refine a treasure like this… Its basically the creation of a realm distilled down into a treasure. No, no wait, not just a realm, but the creation of everything!”
“Did a life form of the third realm create her How strong can they be that they can refine treasures beyond chaos realm!” Lu Yun wondered with amazement.
The little girl hadnt been a connate treasure born from nature, but an artificially created treasure from the hands of another. Just how strong was her maker
“But we have to head over there, no matter what!” Resolution shone in Qing Yus eyes. “Though the Bridge of Forgetfulness is alive now, its spirit isnt strong enough to harness the bridge itself. We still have a chance.
“If we wait until the spirit can fully control the bridge, we wont stand a chance of doing anything at all.”
“Alright,” Lu Yun agreed. He, too, had no plans of heading back to their world right now.
Though his replica had refined hell once over, there were still plenty of flaws in the netherworld due to the missing fragments thatd once made it whole. The Bridge of Forgetfulness and the world itd spawned were indispensable parts of the human dao hell.
“Why didnt you listen” The little girl in a red dress stood in a world of purplish haze, pouting mournfully as she watched the two figures make their way to the bridge. “If youre eaten by the bridge too, that bridge will wake up and come here to eat all the flowers up…”
A continent filled with purple fog and carpeted with hexacolored flowers spanned behind her. She thought for a moment and materialized a black pennant in her hand. Sparkling stars embedded into the pennant exuded the radiance of the celestial bodies in the sky.
“Wait… I dont think this is called the third realm… I think its called Hongmeng” the little girl murmured quizzically to herself. She waved the pennant out of the third realm and sent it into the fourth. 
1. Hongmeng is a metaphor for the "primordial world, primeval chaos" in Chinese creation myths.-