This was such a great game! It blew me away how the audio system worked and really integrated the player into the game! It was honestly really fun and the two 'stories' that happen before everything goes down was really fun and quirky!
(Video at the end if anyone is interested in watching!)
The calls and the environment becoming scarier was super engrossing and enthralling, of course enhanced by the voice system. It was all very well done.
My only suggestions to maybe improve the game in the future would be three things; One is to have a more emotional voices (Though I do realise that getting better voice actors is more expensive and it itself can be hard to do), the first call had the emotion of the caller being really worried about his doggo. The second call did suit the Karen vice of it, could have been more angrier, etc, but it had it's own 'drunk Karen' kind of vibe and was fine overall. Now for the third call; as intriguing and immersive as it was, the sort of emotionlessness of the wife a little bit kind of made it not as immersive. (This is just my opinion though, but I still found it fun and immersive!)
The second thing would be to have more stuff happen in the office and the room in front. The subtle writings were pretty good and really added to the ambience and it was refreshing as not many horror games add the subtle spooks, so really cool that you did! Maybe some life in the police office would also add some amount of immersion, but yeah, more things happening around would add a lot more to the environment, though the stuff that did happen was really well done!
The last thing would be the actual story and also the monster. Building up the story to what it was at a longer pace might have suited it; let the players slowly start to realise what's happening. Unless the players look at the file and look closely, they might not connect the dots; some might even brush off what the first officer said at the beginning because of your really cool mic system and funny stories. And building the story up would also allow the monster at the end to be slowly introduced. Maybe show a hand or a shadow, and then some other scary things that it does, and then at the end, the monster appears and kills the player. A build up would also suit the story rather than having the monster randomly appear and Chidori the player's character.
And as an avid Creepypasta reader, I saw the where your inspirations came from and was really neat to see how you made a game inspired from the story! Overall it was a really great game and tonnes of fun to play, you could make people pay for this and there wouldn't be any complaints. Hope to see if this audio system interaction with the game is developed as it was really cool to use and experience! Do take care and good luck with future projects and anything else!