The dark spirit meddlers, the fallen angelics, can usually fend off one another in a direct contest. They are all in a fight for survival and there may well be predation among spirit meddlers by their brethren when they reach a weakened state and are barely holding on to existence. The predation by another spirit meddler can in fact end their lives, but it is a meager reward because at that point they will be so depleted it will not give enough energy to another such spirit for long enough for them to carry them so they can stand down and relax and rest for a while; it will be a quite temporary source of sustenance and they will have to scramble quickly to find a living host to prey on in order to keep going.
The lost soul human spirits can be set upon by the fallen and be a chronic source of energy and in a state of depletion personally as a consequence, losing so much to their predators. They can usually sustain only two or three such dark spirits, the main factor being that those dark spirit meddlers will fight others off, if too many attempt to gain a foothold. Lost soul human spirits will be jealously guarded as a source of energy, and being in a weakened state themselves from becoming earthbound, will be easy prey in many cases for attack from the dark spirit meddlers. Eventually, the lost soul human spirits may find a human living host and this will provide a safer harbor for them if they can penetrate the energy shield of the aura and take up residence. Unlike the spirit meddlers, human spirits are still given life force energy to sustain them so they are not strict parasites. Whereas the spirit meddlers must have another living source of energy to tap, in order to get something for themselves because they have been cut off from the divine totally, in terms of life support.