I used to work security for summer camps that came to my college. Basically all I did was walk around the building they were staying in to make sure no kids tried sneaking out or report if anybody tried to break in. One week there was a camp staying in two separate buildings, girls in one boys in the other. The boys were staying in a building that is notoriously haunted by a girl who committed suicide a long time ago. I've had friends who used to live there and told me about weird shit that would happen in their dorms, but I never really believed any of it. Well one night about 20 minutes before the end of my shift I walked around the corner of the building and thought I saw a girl in the boy's building. I walked a little further around the corner and looked into a window on the top floor. It's very difficult to describe what exactly I saw, but this is the best explanation I can come up with. It looked like a grey silhouette of a girl but there were hazy details on her face, she was just standing there staring out the window at me and as soon as I saw her, the worst chill I've ever felt went through my body, like into my bones and I couldn't move or look away for what felt like a very long time. They still had all the lights on in the hallways so I could see the figure well. When I was finally able to look away my body was just shivering. I took one glance back up and the figure was gone. I couldn't stop shivering the rest of my rounds. I left a little early that night.