Art: 9/10: It's cool and gothic, honestly the only reason why anyone will stay to read this
Story: 1/10: Can't rant more about this. It started off with a pretty cool premise. Different mysteries and our main character trapped in a toilet, yeah?
The only problem is that our second main character has everything worked out for her. It's pretty much all your typical manga issues: everything being concluded with a simple swing of the knife, a single talk to from our second main character resolves the whole isssue that has been bothering our villains for a Long time, or coaxing enemies into submission; events conveniently happening whenever it suits the author, like if mc1 says not to let side character touch mc2, you know for sure mc2's gonna get touched for sure.
It's all very predictable with the Friend turned into enemy troupe, and enemies turned to friends, most ostensibly by the Mary Sue. Except, in this particular work, the coolest villains whose background story get explored immediately after their defeat will thereafter be flung into the abyss and be forgotten till the author decides to conveniently pop them up again.
Need I also tell you that (spoiler) mc2 gets turned into a fish whenever she touches water? The author conveniently skips all parts about how she bathes, and how she hides that from her parents. I know this whole story is supposed to focus heavily on the school setting, but it's almost as if this world is a vacuum where the only characters are our three mcs. Honestly, there's not an ounce of realism in this world at all.
Character: 1/10 I would give a 0 if that is possible.
Mc2 aka. The girl: can be summarized as lovesick fool, plus radish. Literally, when she goes into a hell where students are tormented by their innermost fear, hers shows up in the form of people calling her a radish. Seriously, does she not have other problems? The author brings the joke too far in terms of constantly reminding us she has oddly shaped feet, making every single character point that out upon meeting. Fun fact: she was only bullied for it in one panel, by that one minor character that showed up only on one page.
This character is unrealistic, stupidly naive, and you'll find everyone falling in love with her for no reason. She has your special Naturo speak no jutsu, except in most cases, you won't find her doing a single thing besides flailing, floundering, worrying needlessly till someone takes pity and treats her nicely. She is the whole flaw in this manga, because you'll find the author pulling every reason out of their ass to make the two other main characters fall in love with her. Absolutely horrendous.
Mc3: the student boy minamoto: believable. It's entirely refreshing how much he stands up for himself and others when the story decides to focus on him. That's a tell on how abused we are as readers, because we're constantly forced to view things from the pov of our pitiful useless mc2. His growth is the one thing that keeps me reading on.
Mc1 the ghost: the highlight of the show. Little titbits about his past keeps getting revealed along the way. Teasing and fun in a way that is not always harmless but completely intriguing, he is the saving grace up until you realise the author has decided to dedicate an entire arc to him playing martyr and playing the role of the villain just to save our useless ignorant mc2 again.
Honestly, let's just stop it with the whole mc2 thing already. I get how useless she is that she needs everyone to protect her, but honestly? This whole story is turning into a self-fulfilment fic where the mc2 self insert is trying to collect a harem of knights to protect her. Frankly, I'd enjoy it much more if the author starts being real and treats this story that way. That's clearly their drift.
Also, I'm not exactly sure on the genre of this manga. Is this romance? Is there supposed to be a love triangle between all the mc? Because with the way mc3's heart goes flying out whenever mc2 does something and mc1 plays the whole role of the darling knight for mc2, I find it dubious that this is even your friendship troupe. I dread the more I read, because this is clearly not the content I signed up for.
Also: misaki: honestly, what can I say? He's that one cockroach that refuses to die and the more he returns, the more he ruins the perfect character you wish the author had left dead in the beginning. Also, he's soft on mc2. Need I say more?
Overall, enjoyment: (0) 1/10. I read this because the anime will be coming in 2020, but I'm left wondering why I wasted my time.