One body, six souls!
Not every soul could control this body. Even though they were all inside it, only one soul could control it. This soul was the main soul, while the other five acted as assistants.
Originally, the position of the main soul belonged to Xuan Shang due to his natural advantage, but due to the transformation brought by Su Ming's blood, the main soul became Su Ming.
If a normal person had six souls in his body, then when the main soul controlled the body, the other five would be in deep sleep. Yet now, the black blood which they had entered was formed by a supreme treasure. Because of it, even if Su Ming acted as the main soul, the other five were awake. They could see and sense everything around him. Besides being unable to control the body, they didn't suffer in any other way.
Preview to next chapter: Dust Burners
I think this is how Su Ming will act if the Abyss Builders are still alive...