Hi all I am new here...
I see there are many different beliefs and opinions here on what demons are, which is always good. I love learning different sides of things from others.
In my understanding though, demonic hauntings are extremely rare on the earth plane, as it is not there natural state of being, they dwell in darkness and void, and can not sustain them selves in an existence so unnatural to them such as the physical plainfor any period of time. Many negative hauntings that some believe are demonic and demons plaguing there house, are often just negative and bitter human souls who were bad in life and have continued on with there negative ways in death.
Negative and scary hauntings can often be the result of no spirit or demon whatsoever, but the result of an individual living person them selves. It is believed by many that people who hold in feelings of suppressed emotional events that might have happened to them from coming out, can build up a dark and oppressive energy, which can result in some very scary and strange phenomena happening, such as apparent poltergeist activity, and Telekinesis, nightmares, and the feeling of being taken over, or a foreboding feeling of someone watching them. Many negative hauntings have been resolved by one of the people living in the location realizing there own suppressed and hidden fears and emotions they might have kept at the back of there subconscious mind, and then dealing with them emotional problems in a positive way, and venting them in a way that doesnt harm others. The core of many hauntings can be in some cases the dark energy coming from the emotions of those living there.
If in the rare event a demon is haunting someone or a place, its good to recognise that demons are not the horned hooved devils of the bible or Torah, they are non human entities that have been born into existence by the actions of other human beings, by such negative things as war, murder, rape and other actions which caused negative emotions, such as fear, hate, intolerance, and envy, amongst others.
Many occultists and people of a spiritual nature dont see demons as "fallen angels", but dark energy forms that have been created by the actions and thoughts of evil and negative human beings on earth, that came from people who live there lives through fear and anger, often via dark rituals, which then manifests its self into the astral world, which in most cases will just be absorbed into the astral, but in rare cases will become strong enough and will form its own will and consciousness and become a thinking aware being.
These demons can occasionally (very occasionally) effect a place or building, if they are powerful enough. These demons are often called "Demonic thought forms" or "Astral Larvae" and even "Elementals" (Not to be mistaken with Nature Spirits)
Its because of these demonic energies that some places can have these problems, which have witnessed murder and other traumatic events or dark rituals, as these energies can linger in the place they happened, and sometimes cause what some may know as a demonic nonhuman haunting. Its why many places that have seen murder and wars seem to have a strange aura, and supernatural things happening in or on them.
Science has proven that everything is energy, and that energy can not be destroyed.
Think of something tragic happening like a mass murder, think of all that hate, anger, fear and suffering that went on within the walls or the land it took place, think of that as energy, negative energy that doesnt just vanish into nothing. It lingers over time, and can even become powerful enough to become conscious of its self, and become thinking, and can feed on other energies around it by attaching it self to someone, causing them people to become what others might call psychic vampires.
Most negative energy is absorbed into the astral, but sometimes as just said, it can be strong enough to be self aware, and will act in the way its nature is, and because it came from an event such as murder, it is going to be evil and negative in nature.
They cant be reasoned with, or bargained with, as they dont think like humans, they are simply a pure negative source of energy, that is being what it was created as. And the only way they can be dealt with is by cutting of its life force that allows it to remain in this world. The energy it requires to live here is fear and hate, people in hauntings often fear what is in there home or become angry, so unwittingly help feed the evil entity that is there.
There are many stories of the people in a haunted house where an evil entity exists standing up to the negative entity and refusing to fear it anymore, and the problem vanished literally over night.
How many times have you walked into a room where a harsh argument had just taken place, and you could feel the atmosphere? And felt somehow uncomfortable, and could cut the atmosphere with a knife? Or have you ever walked into a room when everyone is having fun and are happy and you feel the positive atmosphere and feel comfortable? Well its this kind of energy I am talking about. Its comes from us living people so its important to live life with good and positive emotions and stop doing the things that might cause evil to manifest. We make our own demons, and we and we alone are responsible for them.