Why does Mazikeen from Lucifer so desperately want to get a soul?
She is clever, intelligent, inquisitive. She is emotional and understands emotions in others. She adapts and thinks ahead. She has friends.
What does she expect a "soul" will bring her? Turn her into a mortal human?
Better understanding of human nature? Of human interactions? No, a soul does not bring this (whatever that soul is supposed to be). We have plenty of people that do not get these social contexts and they are not soulless.
Because she would not be "just a daemon" anymore? That would mean that ripping someone's soul turns them into a daemon. But this is not how she was made a daemon in the first place.
So what does she need a soul for?