Alone in the house, I look out the window. I thought I heard a knock, so I walk over to it. I look outside and I see nothing out of the ordinary. A few children playing in the park nearby, an elderly couple taking a stroll just before the sun sets. I go back to my work, assuming it was just a figment of my imagination. Until I hear it again. And again. And again. I look out the window once more, knowing that I didn’t just dream it up this time. But still, I see nothing. Only the children going home as night falls and no couple in sight. I go back to my work. A little heedful now. I hear it again and again. Constantly. As if something, or someone, was trying to tell me something. At the thought, a chill goes down my back. As if a long thin finger swept down my spine. I shudder. It’s as if a presence has settled over the room. Knock. Knock. Knock. As if it was mocking me. Abruptly, it dawns on me. I look over to my mirror and freeze. All too aware that the knocking is coming from there. I’m petrified. I can’t move. Adrenaline rushes through me. After what feels like hours, I finally have the courage to stand up. I walk up to my mirror, never taking my eyes off of it. I look at my reflection. And I see myself blink.