Lately I've been doing some research on Satan and the demonic realm. Granted I'm not fond of it, but there's no harm in gaining an understanding of who the Devil is and how he works. In fact, it's probably unhealthy to ignore it altogether. Why? In 2009, a survey from Christian Post Reporter asked U.S. Christians what they believed about Satan. According to the survey, nearly six out of ten Christians either strongly agreed or somewhat agreed with the statement that Satan "is not a living being but is a symbol of evil.” That is dangerous.
It's important to recognize Satan’s existence because neglecting his existence leads to divorcing the necessity of God’s eternal gift to us. Satan is real and Hell is real, and sadly, people do go there. Satan doesn’t want you to believe he exists, and if you do, he’d prefer you recognize him as some sort of Loony Tunes caricature of himself because it means we aren’t taking him seriously.
Satan can be easily combated if one is equipped with the Holy Spirit and the gifts He gives us, but it's also easy to fall into his traps if we're not careful.
I remember once quoting someone that Satan's number one sin was pride...but I'm not sure I was right for quoting that. I'm wondering if it's fair to suggest that it was equal parts of pride and envy because Satan was jealous of God and strongly jealous of man. He couldn't stand the idea of having to help mankind. He despised Jesus long before Jesus was born into the world.
When it comes to demonic influence on man, it's surprisingly not difficult for it to happen. People do become possessed all the time. It isn't fictional when we think of demonic overtake -- it happens.
Don't be surprised if your dream was something that was actually happening to you. It's not unlikely for them to attack at night during dead hour (around 3 AM). And keep in mind too that Satan isn't trying to go after people who live in sin. He's already got them, he needs no major effort for them. His work is focused on those who are obedient to God. This is why Satan even followed Jesus around the dessert.
My wife and I were on vacation back in 2011. The first day of that trip, we learned that my uncle had shot himself in the head and killed himself. That evening, my wife said, while I was asleep, she opened her eyes and saw our cat, Cecil, staring right back at her (she loves Cecil), but the face was distorted and had an ugly look to it and appeared to be choking. The night after, she says she distinctly heard a voice say "No! Not while they're asleep!" And immediately after that, a wave of relief came by. I don't remember it, but I don't doubt any of it.
When I was in my early teens, I remember waking up to what I thought was an asthma attack (which I have). I'll get them at night sometimes, but this time it was a sharp pain in my chest. There was more to what I was feeling. I began praying and right away, the attack was gone. Typically, I would have needed an inhaler and maybe a use of my nebulizer to clear my chest, but it went instantly through prayer. I wouldn't be surprised if a demon was sitting on my chest tormenting me.
One thing that's typical is even seeing little kids and babies getting fussy when a discussion about certain things arise. I was once listening to a homily at a Sunday Mass and the more we began talking about this subject, the more little kids began to cry and scream. The priest then said "Wait a second..." and the room got quiet immediately. All of the kids just stopped. The priest then went on, "The devil's stirring them all up. When you start preaching on this, this is really typical, so don't be disturbed -- he's just irritating those little kids. You just say a prayer and he'll quiet down."
If we believe in the heavenly world and the works of angels and our guardians, we have to acknowledge the hellish world and the works of demons and our tormenters. Don't be scared of the little morons, but be on guard.