Cold air swept through the room. The curtains didn't flutter; they hung heavy and still. On the screen, the letter 's' began to multiply, filling the white space like a wave of digital insects. Thousands of them poured across the monitor until the screen was a vibrating wall of emerald green.

Seven-year-old Leo found the file on his grandfather’s old desktop, nestled between folders of tax returns and blurry vacation photos. It was titled simply: sssssss.txt .

Leo scrambled for the door, but the handle was cold and slick, as if coated in oil. Behind him, the hissing became a roar.

The hissing grew into a whisper. It sounded like dozens of voices speaking at once, all of them missing their vowels. Leo backed away, but his chair felt bolted to the floor. "Who are you?" he managed to ask.

When he double-clicked it, the screen didn’t show words. Instead, a single line of green text began to crawl across the black notepad window: Ssssss... can you hear the static?

She walked over to the desk and noticed a single piece of paper had printed out during the night. She picked it up. It was covered from top to bottom in a single letter, over and over again.

The door finally swung open. His mother stepped into the dark room and flicked the light switch. The computer was off. The room was empty.