YMMV / After School Nightmare

• Audience-Alienating Ending: The story alienated multiple fan factions with its ending to a degree that they no longer recommend it, for completely different reasons:
  • The people who were reading for the mystery arc, who thought that the final explanation (the story is a metaphor for pregnancy and childbirth) was simply too silly and bizarre, and raised far too many questions about the world building.
  • The shippers, who were unhappy that Mashiro and Sou end up in the real world but with no knowledge of each other or memory of their love. Alternatively they felt the reveal about Sou's siscon issues was too much and turned it into a No Yay, or had preferred Kureha
  • The people who were reading for the exploration of ambiguous gender, who thought that the revelation that Mashiro's gender ambiguity being because they are actually fraternal twin fetuses struggling for possession of one life, meant that the situation was either reactionary in implication or too fantastic to have any possible real-world relevance.
• Broken Base: The manga's character design is seen as really pretty or quite ugly.
• Die for Our Ship: Some people really have it out for Kureha... Sure, she's a Clingy Jealous Girl who finds solace in Mashiro's company because she Does Not Like Men, but still... Poor, poor childhood rape victim Kureha. It's only made even worse by the Draco in Leather Pants status granted to Sou Mizuhashi, Mashiro's other love interest, even when he's kind of a bastard...
• Esoteric Happy Ending: It turns out the entire series takes place in a metaphorical realm designed to prepare the unborn babies in a maternity ward for childbirth. The babies who have already "graduated" are all born safely, but they lose their memories of anything that occurred in the series. As for the ones who haven't, they're wiped from existence (except for Mashiro, who escapes just in time to be born as a girl) as they and/or their mothers are killed in a hospital fire. A scene at the very end shows Mashiro and Sou running into each other years later and having no idea who the other is, teasing readers about possibilities that may never be.
• Fan-Disliked Explanation: Some readers disliked the ending that reveals everything that happened in the series is just a metaphor for pregnancy and childbirth, with the students being unborn children, as they felt it negates everything the characters experienced, especially since they won't remember anything that happened anyway. The explanation given for Mashiro's struggles with gender identity (they're actually a pair of boy-girl twins struggling for possession of one life) also didn't go over well with some fans, partly because it raised a lot of questions on what Kureha's traumatic rape as a child, Sou's incestuous relationship with his sister, or the other students' hang-ups could actually represent.
• Ho Yay:
  • Between Sou and Mashiro, who doesn't belong to either sex but identifies as male. Sometimes. That's sort of the entire point of Mashiro's journey. And by the end, Mashiro identifies as female, full stop. Although it's less that Mashiro "identifies as female" than it is that the unborn sister kills her twin brother to gain full control of the single life they were sharing.
  • Some consider Kureha x Mashiro to be Les Yay.
• Values Dissonance: Mashiro's gender identity is based on a very hard division between masculine and feminine (among other things largely ignoring the concept of homosexuality), to a point it can come across as offensive to some Western readers. And that's before getting into the problems with the ending that reveal that Mashiro technically doesn't have gender issues because they're actually two different people struggling for possession of one life, not one person struggling with their own identity.
• The Woobie: Kureha can certainly be a pain in the ass for some readers, especially those who ship Mashiro with Sou. However, it's hard not to feel bad for her when it's revealed that the impetus for her misandry was being raped as a five-year-old while coming home from school, as well as her father flat-out declaring she was Defiled Forever after the fact.