This was just as fun as the two sequels! It was really cool how there could be two endings depending on how much you washed your face! (And the quick save at the last chapter was a nice add!)
It's only after this when I realised that both in this and the third game that time goes faster when one is looking at the TV.. I was very dumb, but I thought it was both a nice way of showing how watching shows can suck time away and both add a layer of intrigue at how watching the anime is taking over the players' life.
Also it was after playing this that i noticed that Hayami-chan is growing more and more staticy; both in the jumpscares and also in the game poster. Which is really interesting and I'm honestly taking into how much effort and love you've put into your games! It was really fun to play and experience the story and world building so far!
The graphics as usually was neat and added to the overall scariness of the game. Even the small touch of the reverse speech of the TV was really nice!
My only suggestions would be (if you work on another Hayamiverse game) to make things happen in the day time. Rather than one off spoops where Hayami-chan is seen from the balcony, maybe make her pop up more often, or maybe change the environment (which would be a cool way of showing how the character is losing themselves further into Hayami-chan) Seeing a dynamic environment would really sell the surrounds to the player and make it more immersive. Maybe seeeing the character buy Hayami-chan merch, which she uses to possess or maybe seeing litter pile up to show that time has been passing and the character not taking care of themselves would be immersive and more of an incentive for players to explore the house and environment instead of just pointing at the TV to get to the night where things do happen. (Which you implemented into the third game; it was a good implement and I thought it did make it better, but there would have been no reason to look at the kitchen at the last day because players might not be exploring as nothing else really happens during daytime.)
But the way the games are connecting and how you've incorporated the stories, I think is great! I really did enjoy all the games a lot and it was really neat to experience them all and to see how they have improved as well! Glad to have stumbled on this series!