Don't Look Back, It's Looking at You

Have you ever felt like this? When you walk alone in a long alley without street lights late at night, you will feel an inexplicable chill on the back of your neck; in an empty elevator, you always feel that there is another breathing sound standing in the corner; or, when you are staring at the screen to read this text, you catch a glimpse of the shadow behind you that seems... Slightly longer. Don't move. Don't try to identify the source of the sound, don't try to catch the reflection on the wall with your peripheral vision, and don't look back.