In the beginning of the multiverse there was the creator of all, The True God who had created countless universes, realms and worlds. He arranged those worlds for his creations in an order that would ascend with their strength.
If one were to explain how the multiverse was arranged, one would have to look no further than an orange on a tree in an orchard. A universe would be a seed in an orange, which in turn the orange would be the six dimensional structure containing many universes. The flesh of the orange would be the void between the universes. If one were to raise their cultivation high enough, they could break from the seed and escape into the infinite sixth dimensional void where many spectacular godly creatures and realms would appear.
Those oranges were the lower realms where most mortals and lower ranked Gods would appear.
However, if one spectacular prodigy were to reach a cultivation beyond the Gods, he would break from the orange, and into the orchard which held twenty dimensions with each infinite infinites larger than the one below and before.
If a cultivator from a seed or lower dimension where to somehow arrive in a higher dimension without breaking through their cultivation's limits or without some form of protection from the dimensional pressure, their cultivation, body, and immortal soul would be sucked in and absorbed, leaving nothing behind.
The dimensions went as such.
The first three were space. The fourth was time. These four dimensions were where you would find the vast majority of mortals and beasts, all living their lives ignorant of the gods above, who could snuff the universe out like stepping on an ant. The fifth and sixth were imagination. Anything one could possibly dream or think of resided in these two layered dimensions. This was where cultivators, Divine Beasts and Gods resided in their own personal realms cultivating and gaining power and artifacts from the Gods who had broke through the dimensions into the higher dimensions.
The seventh and higher dimensions were dangerous realms where only True Gods and Demons could exist without their very conceptual existence being obliterated like dust in the wind. The beings that walked these planes were so large, just existing near the lower dimensions would erase them from space and time and existence.
This brings us to one man. No, to call him a man was foolish. He was a True God who had ascended thirteen dimensions and had unfathomable cultivation. His very being could suppress everything and everyone in existence.
As of now he sat in a black void, everywhere and nowhere as space was nonexistent here. It was a non factor.
He wore a light blue robe the color of a spring sky with silver runes all over it. They glowed with immense power. He had long diamond white hair and ice blue eyes that seemed to contain the infinite sky within them. His skin was as white and clear as Cloud Jade.
There was a great silence around him as a silence before a True God would be. His energy had completely filled the seventeenth dimensional plane of existence, and was in the process of breaking through to the eighteenth. It should be noted that he did not have a physical body in an actual sense, as the man cultivating in the black void was just the conceptual projection of his immortal existence.
He had gained many names throughout his ascension, but the one he kept was Gu Beixuan, his first name from when he was born into the Gu family in a small world in the edge of the local universe quintillions of years ago.
A wide smile spread across his face as he felt a Tribulation oncoming. It was his chance to improve his cultivation to an even higher realm. He had long passed any and all recorded cultivation levels and existed only to rise higher and achieve a new layer to his existence.
As he attempted to ascend the dimension shook and rumbled as it resisted his power of ascension.
He could do it!
As he felt his existence rise and expand, suddenly he felt a massive hand grab hold of his existence and tighten it's grip, Some being from the upper realm was suppressing his ascension.
He struggled intensely, lashing out with conceptual, spacetime, existence deleting attacks, but the hand was untouched as it squeezed him tightly, crushing his very being.
Then he heard a voice speak to him.
"Gu Beixuan! This God King will not permit your ascension! Be suppressed and accept your end!" The voice cried out and the feeling of the hand tightened even more as he felt his very existence being crushed.
This could not be happening. Gu Beixuan would not allow himself to be suppressed and killed!
Resisting as best he could, Gu Beixuan fought back with all of his being. However, this was to no avail as he was finally fully suppressed and thrown down through the dimensions and out of the multiverse being sealed and suppressed.
Landing in the Sealing dimension of Ddraig accidentally as an incorporeal spirit, he was sealed within Issei's hand unknowingly.
How this will effect Issei and Ddraig, no one knew for sure.