Alright guys. please read this if you ever wondered this question. THIS IS SOLELY PERSONAL REASONING AND IS NOT SCIENTIFICALLY PROVEN.
Now, as we know, we find some things sch as murder, and all around killing of other humans to be disturbing. Why?
With murder, we can not take the idea that someone else killed another human being. we find it odd, scary, we wonder if we'll be next, or what they were thinking. Horror stories always have someone die for this reason. Its the same as feeling betrayed. We feel as if the other person, even of we did not know them, has betrayed us by committing murder. plus. its just plain wrong.
And now we move onto the next subject: Things being creepy.
Why do we find somethings creepy, others not? Something being creepy is simply saying that its not right. its not supposed to be that way. such as a flash of an image on your computer, the sound of animals you can not see moving at night, the tap of a branch against your window. These things guide our mind to places it shouldn't go, making the situation even worse for the person experiencing it. For example: The game Suicide Mouse. The colours are gray and black, colours that are murky and almost never commonly seen in cheerful games. The doors lead to warnings such as, "I'm dead, and your're next," "Get out," or "Save yourself." Things no one ever wants to hear. This also makes us wonder, "save ourselves from what? Why do we need to get out? Why are we the next to die?" The game itself does not explain this, but there is that element of human curiosity that will drive to find the disturbing, such as the Rake, or Slender man, or other mythical horror icons we think we can only dream of. I bet you're slightly disturbed right now, realizing that this might actually be true. I think it is. As humanity sees it, things like these games and stories are creepy or disturbing because they're not CHEERFUL. Cheerfulness seems to be of the utmost importance now a days, and that is good. But other reason these are so "disturbing" is because they somehow got through our wall of safety. Of cheerfulness. And the fact that it will never stop. But that may not be a bad thing for some who like this kind of stuff.
One more thing we find disturbing: The idea of another human being able to do things we can not. Such as move objects with only their mind, or being able to speak to us in our own minds. This disturbs us because we do not know what these people could do. could they control us? Break us of free will? Or make all of the above paragraph our daily lives with no cheerfulness at all!? This, I'm happy to say, has not been proven a reality, yet.
Another thing to be disused is why other people think different things are creepy or not. The thing with this is that people have different personal experiences. for example: I am terrified of real life gore, while i have a friend who can not stand animated gore but thinks the SAW movies are just fine. Now, this is because she's USED to gore. she grew up with horror movies, while the first horror related anything i ever watched was a blooper from SAW. And that was about a year ago. I am not saying this is garenteed, i'm just saying this could be a possible reason.
People also fear the unknown. A black background with only the glean of two red eyes peaking out, or the blood red outline of a character or person we might know or find familiar, yet it has that feeling of, "something is horribly wrong." That's also why we seem to have an almost natural, whether it be strong or not, fear of the dark. Because anyone could be behind it. Its the same with getting a phone call, answering and only hearing white noise static, or someone breathing before the line goes dead. This scares us because we dont. Know. Why. We dont know why we got the call, who the person breathing was, or where the noise came from. The unknown is scary.
which ties into our last subject. Being alone. The thought of being absolutely alone is terrifying, no? It means we're the only ones left, no one can help us, if we screw up its GAME OVER with no replay!!! and, being the humans that we are, we know that failing is going to happen. And, how this ties into the last paragraph is the fact that most people are not only scared of both things apart from each other, the fear of the dark and of being alone, but more times than not, both. Being alone in the unknown, in the dark. With no way to the light but to walk and hope you dont fall. Its absolutely terrifying.
I hope this helps a bit. If you want me to explain about another subject, please do feel free to note me or ask me through comments.