For normal people, it was similar to Anais's Dream Scripture Maiden technique in which she entered the dreams of others and consumed them to increase her cultivation; just a more upgraded version, as it affected the soul instead of the psyche and consumed the disturbance caused to increase the cultivation.
But for me, who had the Gluttonous Shadow, the devourer of all things, the Drunken Dream Mantra got upgraded to something extra.
I could not only cause disturbance in the soul of others but also, using Gluttonous Shadow, could devour a part of their soul.
The effect multiplied when done to a significantly weakened target, either physically or mentally.
It seemed like a despicable act, as I would be devouring the souls of others. Still, I just had to control the Gluttonous Shadow and absorb only the soul power of the soul before letting go the soul so that it could enter the cycle of reincarnation.