Sadly, the summary of this story does not tell us anything about the story itself.
Have you ever stared at your reflection in a mirror? Stared and stared and stared? Expecting it to move differently than yourself? If you caught your reflection moving differently in the slightest way, blinking when you didn't, twitching when you didn't, doing something you did not do, then... what would it mean?
The way I see it, there are 2 kinds of people in the world:
1) Those who are terrified their reflection might move. It would negate everything you thought you knew. It would mean the supernatural really did exist. It would mean all those horror movies could come true. It would mean anything could happen.
2) Those who are hoping their reflection might move. It would negate everything you had ever been told. It would mean the supernatural really did exist. It would mean all those things you have been dreaming of could come true. It would mean anything could happen.
Either way, experiencing your reflection moving differently to yourself, even in the slightest way, even only once, would change your life forever.
Have you ever stared? Stared and stared and stared? I have. And I used to do so for the longest time. It took quite a while for me to realize (and truly believe) that my reflection would never move. It couldn't. It wasn't another being behind the glass. It was just light particles reflecting off me, reflecting off the metal coating behind the glass, into my eye. That's when I stopped staring.
So, you see, it wasn't until my reflection actually did move differently than expected (and quite a bit so), that I realized I didn't belong to the 2 kinds of people mentioned above, but to an unexpected 3rd kind.