The main difference between a demon and a negative supernatural experience is the intensity; a NSE might be scary and awful, but a demon will have every muscle in your body wanting to run out of fear. You are in the presence of pure evil. It wants to hurt you. There’s no other way to describe it. If you were asked, “Did you feel you were in the presence of true evil?” and you answer no, then it’s not a demon. If you think your NSE was bad, then imagine it kicked up to 100. That’s a demonic experience.
Old Hag/Mara experience: this is when you’re experiencing sleep paralysis and see a shadow or similar figure in your room who then either presses on your neck or chest to cut off your airway. David Hufford’s The Terror that Comes in the Night is the definitive text on the matter, so if this sounds familiar, check him out. This is a very common experience and largely what people think is a demon because of the terror they feel. It’s hard to say if this is a body process (ever had hypnogogic hallucinations? They’re weird as hell but apparently quite normal) or a spirit experience. It’s possible there’s overlap.
Malevolent spirits are simply not benign, good spirits. They’re often angry or wishing harm on living people, sucking the energy away from us to manifest in a room. Some examples are angry human spirits, dybbuks, and shadow people. Much more research will need to be done on my part to give a fuller idea about what dybbuks and shadow people can fully do, but it appears they can possess people, which makes them very dangerous. Their phenomena is similar to that of the demonic but it seems to be at a lower level. Dybbuks are thought to be evil, wandering souls in Jewish folklore and shadow people are well-known by the paranormal community. Perhaps these are even the same creatures (another post will cross-reference their abilities).
People thinking they’ve had sex with a demon are wrong-it’s something else, I guarantee it. I had a spirit (what I believe is either a jinn or a familiar who has tried to touch me since I was a teenager, so yes, I know the feeling.) Demons are creatures so unlike us, who do not have interest in our flesh except to hurt us. They HATE us. I won’t get into Christian doctrine as to why because the truth is, we don’t know what these creatures are for sure (though religion provides an answer, it’s impossible to tell if it’s the correct answer). All we know is how they make us feel when they’re nearby and what can happen if they aren’t dealt with. I only use the word “demon” because that’s how our culture understands them. Succubi (female sexual spirit) and incubi (male sexual spirit) are thought to be demons, but according to Father Sinistrari from the 17th century, they are not quite demons because another thing that separates demons in general from other types of spirits is their reaction to holy items (Sinistrari). Succubi and incubi are unaffected by such things and appear to possess free will, also not associated with the demonic (Sinistrari). Demons are bound by rules. Succubi and incubi might even be jinn or fairies, though they seem more focused on sexuality so perhaps not exactly, though they display some of the same characteristics (another post will outline this theory.)
It’s an easy mistake to make. I thought my experience was demonic in nature but through my Master’s research, I realized I was wrong because the patterns in my case didn’t line up with what’s reported with demons so in reevaluating, I understood that what happened to me is oddly common (people have reached out to me with reports of a similar experience) and it involved mirrors in my room pointed at my bed. My professional advice: do not have mirrors in your bedroom; they’re thought of in the occult world as portals. Take them out or cover them up.
Supernatural experiences are scary; I created my classification systems to help people as a checklist of demonic activity. If you think you might have a demon problem, use the classification systems I put on here. They aren’t completely comprehensive, but they’ve covered most of recorded demonic phenomena that currently exists. I’m always adding to it as I discover more abilities of demons.
Hufford, David. 1982. The Terror That Comes in the Night.
Jaye, Victoria, “In the Presence of Evil: Demonic Perception Narratives” (2021). All Graduate Plan B and other Reports. 1563.
Sinistrari, Ludovico. 1875. Demoniality.