The manga in question is "It's a Little Late, but I've Fallen in Love with My Childhood Friend" (imasara desu ga osananajimi wo suki ni natte shimaimashita).
The story initially 
starts out as this extremely cutesy story of a highschool girl realising she's fallen for her childhood friend and her subsequent efforts at getting closer to said childhood friend. Now, when I say this starts out cutesy I'm not exaggerating. It's very cutesy 
and full of fluff 
. It feels like the type of manga where the MC and her crush holding hands would be treated as a major romantic development.
But come chapter 21, disaster strikes.
It is revealed that one of the side characters had been fricking our MC's object of affection 
. Yep, this is no longer a manga about two cutesy virgins getting closer to each other. Then the POV entirely shifts towards the side girl and it becomes a depressing story of how this girl is fricking our guy in order to distract herself from her fricked up family situation 
. This is a complete tonal shift from how the manga was for the past 20 or so chapters.
Suffice to say the fans were not pleased 
( as you can guess from 10x increase in comments on mangadex for chapter 21 
). The show gets bombared with negative reviews taking its ratings from an impressive 9 to a 6 with people making accounts just to shit on the author 
.
Some comments from the chapter 21 meltdown thread. :meltdown
Hey, I just said that.
Why would you introduce conflict in an already perfect wholesome series? Wtf author?
Oh wait, it's the same fricking author who did white album 2, no surprise.
Apparently, this author has done it before 
.
Bro, frick this guy
Everytime a manga post gets like 100 comments in 2 hours it's either the death of a shonen jump character, someone confessing, or problematic shit suddenly happen outta nowhere lmao
Lmao I saw the post at 3 hours and over 700 upmarseys and thought, "oh shit she must've confessed this chapter." Boy was I wrong
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The short and simple answer is no. Of course it's a common route for romance to take, though common shouldn't be conflated with good. Fricking heck it just sucks.
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Is she actually a girlfailure if the world (author) actively shits on her?
She is now a girlsurvivor
Put thru the bs of her friends and the author
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Well, was nice while it lasted, will drop it here. What a shit development. Throwing a wholesome story out the window with just an unnecessary love triangle drama. Sad to see.
Exactly. On top of it the premise didn't hint any of this. Rather the premise had been set on a short wholesome romcom. So the drama was really unexpected and this chapter is so sudden.
The seethe continues into subsequent chapters months afterwards. 
If the author wanted to write this story why did they bother with the first 20 chapters?
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We've gone off the rails but I'm committed to seeing where we are going
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Somehow, it keeps getting worse. I'm hopping off. This isn't even a train wreck I want to see.
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I feel like I've been NTRed out of a wholesome story. I'll never trust again.
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Like I've read through a lot but this tonal shift into some bootleg Boy's Abyss (surprising since Boy's Abyss was... something too) is so butt. How do you pivot something this badly.
From chapter 25 discussions 
.
She deserves better. Mangaka cooked and burned down the kitchen
Shouldve drawn hentai tbh
Normally I'd be appalled by the suggestion.
But for once I agree completely.
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From chapter 27 discussions.
He's using gutter oil.
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This has turned into a whole different story that the title don't fit anymore
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Similar reactions on Mangadex 
.
https://mangadex.org/title/cf1c93cc-4bb5-4311-b926-0f02ad123ad2
/a/utists react
https://desuarchive.org/a/thread/269799330/#269799330
NTR is the law of the world, simple as that.
heartbreaking, praying she goes postal
I might actually pick up this manga if this happens.
Lmao
Childhoodfriends only exist to get BTFO by the new girl that comes out of nowhere
TRVKE 
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Imagine these people trying to read a proper unillustrated novel with multiple POVs. Or anything written from the POV of an antihero.
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my neighbor berserk is a thing
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!bookworms thoughts on this?, is this unique to weebslop for the time being, because of course western novelists love their "tragic villain" and "everyone is evil in this grimdark world" tropes in 21st-century westoid literature, see ASOIAF.
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The whole "tragic villain" thing is very popular in Japslop and Westslop nowadays, while true grimdark is something that's being phased out everywhere due to its many problematic features. Epic fantasy overall is pretty much dying,
ASOIAF was first written in the 90s. It remains a product of a better era of writing, one before the contemporary wave of romantic fanfiction and YA slop authors came in. The current scene is much duller and easier to read, mostly since moids have been reading less so the genre is increasingly dominated by foids. Self-insert stories are super popular, and new authors are drawing more from cartoons, video games, and tv-shows than they do from fantasy novels or actual lit.
"Serious" critique in fantasy boils down to whether or not enough minority/women characters were represented and if they did enough cool things. If they ended up dying or being rated that is going to be called an example of Fridging and therefore bad because they believe TV Tropes is academia. As a result authors have to tiptoe through a minefield when it comes to representation and portrayals of marginalized identities, often relying on goodwill and vouches from approved figures whenever they do so.
GRRM made the right decision when he denounced the G*mergate movement of genre fiction, Sad/Rabid Puppies, but I think he didn't disagree with a lot of their points. They were just too neurodivergent and didn't understand they were up against a cabal of authors, reviewers, and publishers that is very hard for any aspiring author to avoid.
tl;dr: Genre Fiction in the East and the West has fallen, billion must reread books from the previous century.
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You can just say foids.
Edit: nevermind you did.
Remember, avoid the foid
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That's great and all, but I asked for my burger without cheese.
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They do and they always feel the need to shit up discourse with the most abysmal surface level "takes" on the subject matter nonstop 24/7
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