Unhappy Medium by Elizabeth Cody Kimmel

be some kind of negative entity.”
    “Like a demon?” I asked, my voice shaking.
    “That’s just a word, Kat,” Orin said. “Not everyone would call it that. I don’t even know if I believe in demons. This is
     a negative entity of some kind. It’s not your friend. It’s not something that has ever been human. An entity like this can
     go after a person in two ways. If the person is weak for some reason, the entity could gradually take control of a portion
     of their personality. It could encourage that person to behave violently. Everyone has free will, mind you. But if the entity
     could find someone weak — someone who didn’t need too much of a push to become a violent person — it would try to take advantage
     of that person. Take control.”
    “You mean possession, don’t you,” I said, the very word sending a chill up my spine. “You’re talking about an entity that
     can posses a person.”
    “Possibly. There’s no black or white, here, Kat. A person couldn’t just be taken over completely against his or her will.
     The violent impulses have to be there already. But in a subtle way, yes. I’m guessing this is the kind of entity that could
     have a powerfully persuasive force on a vulnerable human being.”
    “So the woman in the room wasn’t murdered by the black cloud.”
    “Not directly, no. She was probably with someone else. Someone who was already unstable, and the entity knew it and brought
     it under its control. Urged it to harm her. That would be one way for it to feed.”
    I swallowed. “What would the other way for the entity to feed be?”
    “The other way would be through someone who is psychically open to the spirit world,” Orin said very quietly.
    “A medium,” I said. “Me.”
    “There was a pretty famous case once … this reminds me of it. An entity based in the top floor of a house in Connecticut.
     These things don’t seem to travel — they’re specific to a certain location, and they have to take what comes. And they tend
     to stay exactly where their last host left them. An entity could wait for centuries for a vulnerable human to cross its path.”
    “But in a hotel …”
    “A much bigger selection, yes,” Orin said. “This thing in the Connecticut house, it had been thought by some to be responsible
     for the previous owner’s madness. The man had always been unpleasant, but one night he went over the edge. The next owner
     of the house, a lady who turned out to be very slightly sensitive psychically — just felt there was something wrong with the
     bedroom. She felt sick when she was there — she got headaches and felt on edge.”
    Like Jac’s mom,
I thought. Which meant she was slightly psychic too. And she didn’t even know it.
    “So she called in a medium — I know the guy, actually. He could sense the entity, and the thing knew it. It went straight
     at him in a full-out attack. Because he had opened himself to receive spirit energy, the thing was able to jump right into
     him. Tried to get him to throw himself down a staircase.”
    I had a chilling memory of the black cloud pushing me toward the window. I told Orin about it.
    “So did that really happen to me, or did I dream it?” I asked.
    “Both, I think,” Orin said. “You were already in tune with the thing, and sensing it in your sleep. Human spirits can leave
     their bodies during sleep — it’s very natural — most of us do it all the time and never know it. You would have been incredibly
     vulnerable to it, Kat, if you were in that state, out of your body on the astral plane, and it came at you.”
    “But it didn’t get me. I used the energy blocks you taught me, and somehow I got away,” I said, my voice wavering.
    I wanted Orin to tell me that I was safe now. That I had proved my power — that I wasn’t in danger.
    “Kat, this thing has seen you, and come at you. It’s got you in its sights now. Because of your psychic abilities, you’re
     directly vulnerable to it,