YMMV / Drifting Classroom

• Anvilicious:
  • The mutants play a movie that shows humanity was responsible for the world becoming a wasteland.
  • Gamo says to a returning Yu to please inform everyone that the wasteland could be avoided.
• Complete Monster: In this story taking place After the End, some people are driven to violence out of despair or survival, but two characters proved themselves to be evil for the sake of evil:
  • Kyusaku Sekiya was originally a friendly deliveryman who is revealed to have a penchant for harming children. After he is brought to the future, Sekiya threatens anyone who comes close to the kitchen, even burning alive the teachers who tried to reason with him. After a boy attempts to save a girl who was taken as a hostage, Sekiya fatally stabs him, and after killing the boy, Sekiya travels through several classrooms while beating innocent students and stealing their lunches while demanding that they cry, informing them that he is perfectly fine with allowing them to simply starve to death. Seemingly defeated by the hero Sho Takamatsu, Sekiya threatens to stab a three-year-old if the students didn't obey him. Fighting against a giant centipede, Sekiya throws a boy at it and leaves him to be Eaten Alive. Traumatized by the experience which caused him to have a harmless child-like personality, Sekiya comes back to his senses after a boy pushes him down the stairs and forces him to swallow a strange mushroom, which ends up converting him and other children into spider-like mutants. Taking control of the school and turning it into a military-like dictatorship, Sekiya trains the boys to be his own Child Soldiers and sends them to their deaths when the mutants attack the school, while escaping with the food supply.
  • Scar Kid, the Arc Villain for Volume 5, is a budding psychopath and a fearmonger who leads a rebellion against Sho Takamatsu in the midst of a bubonic plague outbreak, igniting a war between the students. Starting his reign of terror by burning patient zero alive and trapping all of those who were close or merely affiliated with Sho inside a building, Scar Kid wants to burn them alive to reduce the school population by half, with his soldiers not above executing their own. Realizing that he himself is infected, Scar Kid touches Sho to spread the plague further, declaring that if he is infected, then everyone should also die a slow and painful death. Even after discovering his infection, Scar Kid still burns the building and orders his boys to throw spears and rocks at the windows to stop the students from escaping alive. Not warning his army about his infection on purpose, they also die from the plague before Scar Kid himself succumbs to The Black Death.
• Hard-to-Adapt Work: The premise of an entire elementary school being transported into a deadly post-apocalyptic future filled with monsters and mutants that want to kill you is played rather seriously, with multiple adults and kids shown committing suicide out of despair. It's no wonder there was never an anime adaptation. The two live-action adaptations take great liberties with the story and are comparatively Lighter and Softer.
• Memetic Mutation: The manga's art style is notable for how it depicts shocked expressions in an over-the-top way, to the point that they've been parodied in other anime and manga.
• Too Bleak, Stopped Caring: With the prevalence of Anyone Can Die (especially with regards to the kids), and the bleak situation driving many characters to violence, it's hard to really stay emotionally invested in the characters and their plight.
• Values Dissonance:
  • When Princess asks to become the leader of the kids, Gamo objects. Why? Because she is an evil bitch? No. Because she is a woman. And that women are apparently too sensitive to make serious decisions.
  • How about the eugenics argument in the mutant leader's speech about how part of what caused the end of the world was how modern medicine prevented the weak from being "weeded out"? You could chalk it up to him just spouting the mutants' obsession about the strong surviving like they do to themselves, but since it's used as part of the Green Aesop, it kinda seems like the moral is supposed to be taken at face value.
• What Do You Mean, It's for Kids?: You'd think that a manga like this that features tons of nightmare fuel, graphic violence and death all involving small children would be classified as Seinen, right? Wrong, it ran in a shonen magazine.

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