From late autumn until the snow melted, I shared a big, creaky house with three other students. One afternoon, I was alone, stacking books on a shelf in the living room. I clearly heard the deep, familiar cough of my roommate’s brother, Leo, right behind me. I wasn’t surprised, as he visited often and usually just walked in. But when I spun around, the room was empty. I searched the whole house and found all the doors still locked from the inside.
Another time, I was away for a full weekend visiting my parents. Everyone else had travel plans too, except for Sam, who stayed at the house with his girlfriend, Cara. When I got back Sunday evening, Sam met me at the door. He looked confused and asked why I had been pacing in the upstairs hall on Saturday. I told him I had been gone since Friday morning. He just stared at me, his face growing pale.