I feel this is an extremely important topic, because it explains the Jekyll & Hyde phenomenon, that many especially psychic and intutive people sometimes (especially when they are still in the process of waking-up) display and why they are more targeted and are more likely to get possessed than a not so psychic person. Negative spiritual/astral entities look for the bodies that they can cause the most chaos, confusion and disruption with or that allow them to drain the most life force from others. Different entities have different agendas not every negative entitiy has the same agenda. The body of an Indigo or a Lightworker that has psychic or other extra-ordinary powers (high IQ, exceptional beauty for seduction, or a lot of charm for deception and cunning etc.) can cause above average havoc and give the entitiy a huge advantage in their hunt for life force (which is pure creative energy).
I would like to start you off with an article from my personal website on Shove-Ins:
Next I would like to recommend the book ''Body Snatchers'' by Susan Reed to you:
Short summary of Susan's book by James Bartley, if you do not want to read the entire thing ( I recommend to read it all though if you have the time):
This ad goes away when you register.
and last but not least the very informative lecture by James Bartley from the 2007 UFO Conference in Roswell, NM: