I am going to make a YouTube video over this game tomorrow, but I really enjoyed this game and this is my thoughts on what I thought the game was.
I believe this game is symbolical of depression. The man feels like a mere reflection of himself, and time is simply passing him by, shown by just how fast the clock hands move and the speed of the sun rising. As for the creature, I feel that it is the personification of his depression, as if he's being kept there against his will. Taking that into account, the things the man says when you click on items are POSSIBLY not only true in a literal sense, but also true in a symbolical sense. AS for what's happening in the game, you play as a reflection? So, you're essentially not a real person, which is why he states that he's 'No one.'. Maybe that's a bit of a stretch, but that's what I got from it. And for him shattering the mirror, I see that as him escaping from within the confines of the little world that he is trapped in, with the world being within the mirror itself. That's why I believe the smile that he see's in the reflection is not actually him, but the ALTERNATE version of him that resides on the OTHER side of the mirror world. And by him shattering the mirror, he finds that he has essentially escaped the depressing confines of that mirror world, and is now living the life that his smiling counterpart possesses.
This whole theory may be a huge stretch, as while playing the game I've only made but surface level assumptions. Plus, having no audio while playing didn't help either. I'd say SFX and Music set the tone for just about any horror game, lmao. Anyway. Good game, bruh.