When I was 13, I was living in Northern London. We lived in a small flat at the time. I was happy because I had a pretty good life at the time.
One of my very best friends, Cristina, loved to stay over, and was over often. One night, I took off my necklace, a present from my mother, and started to play videogames. I told her not to touch it. She had wanted to do a séance earlier, but I told her no. So she said okay, and went to the bathroom.
After an hour, it was quiet, and I finally heard a whooshing noise. I turned around and there she was, using my necklace and a piece of paper as a makeshift Ouija Board. I pulled it out and burned it. She left, and everything was fine for awhile. After a week, things turned bad.
I would wake up after feeling like something was choking me, and scratches and things would appear on me randomly. Then it got really bad. I had a perfect memory, but all of a sudden, I couldn't remember where I was or how I had gotten there. I said things to people that I would never say. I attacked my mother and younger sister.
My sister took action and talked to a local priest and he agreed to perform an exorcism. During this, I apparently attacked everyone close to me and said things that I never hope to hear again. It was the worst experience of my life.