You don't have to introduce yourself, I already know who you are. You might think: "How so? I'm just another person on the Internet, and I'm just reading this 'story', right?" Or you might be the idiot and think: "BANANAS."
No, that is not my point. But fine, if you want to pretend this is just another "story" you stumbled across on the Internet, then leave and continue to be the mindless idiot you already were.
Oh? You're still here? You must be smarter than I thought, and for that, I suppose I'll have to introduce myself.
I am not a nightmare. Nightmares are simply figments of the human imagination. Nightmares are not real.
You know what's real though? I know you aren't real. You are simply a mask, you are made up of several in fact, all to disguise that inner you. This is me, of course, and I am real.
Have you ever wanted to hurt someone on purpose? Not for revenge, but for the pleasure of it? Don't deny it, I am you after all. I know how you think, and while you think you're a good person at heart, well, that's a lie.
I can remember you laughing at other people's pain, faking a smile and looking away whenever you saw trouble. I know you keep these memories in the back of your mind, maybe you've forgotten, or maybe you haven't, but either way, I know what I saw, and I like it.
People seem to have many identities, yes? That's another lie you created. There are only two: you and me. You exist to hide me, while I am really you. You don't want others to know your true side, so you hide it with compassion and love. Disgusting and sad, really.
I will always exist in you, I will always be you, your dark side of your mind, your sadistic feelings, and you know they are there, in your mind, in our minds.
I go by another name though, one that is easier for you to remember, and that is Double Identity, though, I do have another name, what was it? Oh, that's right, Insanity.
Which is the real you then, this truth or your lies?