I don't think I can quite articulate fully how much of a boring film this is except for ironically laughing at some terrible line delivery and bad effects. It made me feel like I wanted to write about how bad it was however so it did *something*.
Short review: Don't watch, It's really not worth 1h 40 unless you want background noise that doesn't really matter.
Long review with full movie spoilers: The opening was the coldest of cold, interesting somewhat but it leaves much to be desired. As the movie progresses, however, it just continues to not deliver on any kind of interest except for flakes of what one would *like* to see, but don't get done or thought of.
The whole plot can just be solved by characters just shutting their mouths and not talking, but no we *need* to have these people killed by them being stupid and blurting out her name. Sometimes in films that's fine if you can see some cool effects or other parts of a film to get attached to at least, but this doesn't even deliver on anything at all. Somewhat decent makeup work but that's about as much credit I can give. The exploded eyes don't *quite* look right but it's nothing goofy bad, just that you can kind of tell it's not real.
The director was *not* good so everything else tumbles down with it, for example, usually good actors in other series who are featured in this give some really bad performances. I've seen Inaba Yu give some amazing performances in Sing in Love and other films/series, but it seemed rather obvious he wasn't given all too much to work with or given little to no direction.
The writing was really something else in terms of how much it missed it's own mark of what it tried to be. None of the characters have much behind them except for the reporter and it's a bit ridiculous how little anything happens to any of them of interest. You just get told something happened either to them or about someone, and go " what? " before it moves on and you don't get anything else. Haruo's conflict with his brother gets brought up twice in such small segments, and then we never see or hear of any of that again, it's like that for basically everything that happens. There's even a whole character death that happens that you don't even see and just get told about in passing after the fact, which was stupid? I genuinely had to ask the friend I was watching it with if I hadn't just gone insane and somehow blocked it out of my brain. It's almost like they couldn't get the actor back to do the scene so they had to hurridly pretend it happened.
Generally how the writing went is that it tells a thing to your face, expecting that to be enough to make a character have background, and then it's never spoken of again and neither do characters reflect on it.
As just a personal opinion, I believe it suffers with having too much to get done in it's runtime, something that may have been nicely fixed if they took out the amount of characters involved and simply let the audience have more time to settle into their character. There are gleams of what could have been in there but none of it comes to reality so you're left with a deflated balloon of a movie.
The ending was rubbish, as, quite literally, it just ends with no significance other than the implication that the main guy dies perhaps. Just a cut to credits. Nothing else. The concept of her hitting her head and forgetting the demon's name and what experiences she had with Haruo was good on paper but executed so awkwardly. The taste of the burnt fish was also strange to have been the thing to come back since she's known her own friend who died at the beginning for much longer. Having a callback to the friend would have been nice rather than her promising she'd remember her and then clearly not doing so for the whole rest of the movie's runtime (unless this is a metaphor of some kind in Japan to taste fish or whatever it was, then feel free to correct me and I will amend my review).
In conclusion, It's a mess of a movie and super not worth your time unless you want to see it as mildly ironically entertaining. I had ironic enjoyment out of watching it by giggling about it with a friend of mine, but man that's 1h39m I'm not getting back. Don't bother with it. Stay clear.