Is demon possession real

Well people certainly go into a state of mind that is outside of who they really are. How they came about that state of mind is of no consequence to the individual, seems you maybe asking if demonic forces are collaborative in their efforts. Yes they are, but not directly. They are summarized with the conception of Devil

Demonic posession is mythological religious construct(LIE) that was created as an umbrella label for things the people did not understand..Mostly it was and is still used to describe mental and physical illness..

Schizophrenia, Severe mental retardation, Tourette's disorder, Obsessive-compulsive disorder,Narcolepsy, Dementia ,Autistic disorder, Epileptic disorders,multiple personality disorders,Tumors ,Large(purple/redish)birth marks,Birth defects and deformities were all classed as forms of demonic possession under the Roman Catholic Church.

People who suffered from such forms of this so-called demonic possession were frequently banished,imprisoned and/or executed by the church if an exorcism was not successful..

Now things like medication and therapy are used to successfully treat such illnesses and the days of holy water,holy waffers, crucifixes,robes,big hats,torches,pitch forks, physical torture,mutilation,and midnight burnings at the stake have been seen for what they were,the twisted and immoral practices of religious lunatics who suffered from their own delusional disorders and sadistic fetishes.