The SSS class world that the Ancient God of Chaos Lord Hunluan and the World Eater, Lord An Shizhe, had entered is an upper class ancient world in which cultivation is the main and they were directly connected to Vearth. Most of the beings in these stars knew about the existence of Vearth which is said to be the star where most gods live. With the strength of the two ancient gods, having a place in this world is simple. As for why the soul fragments of their son and his husband were with them, they were begged to be spared.
The only way not to be killed or devoured by the main soul is to seek help from the ancient god of chaos who can allow them to be reborn and be no longer a part of the original. They were given a task for this one chance of survival. They need to pretend to be the God of Destruction and his other half, the Sovereign God of Void and Darkness to bait these two entities Lord Hunluan wanted to capture.
