Follow TV Tropes


Manga / Sekai Oni

Go To
Sekai Oni follows fourteen-year-old Azuma who has developed Alice in Mirrorland syndrome, a condition that causes her to see "hallucinations" in a reflected surface, through years of emotional, physical, and sexual abuse at the hands of her family.

One day, Azuma is pulled into her mirror and into "Wonderland", where she meets others with Alice in Mirrorland syndrome, called Alices. She and the others are tasked with fighting monsters called world devils each night for six nights in order to save the world. They soon learn that upon killing a world devil, someone they have frequently interacted with will die. Azuma vows to kill the rest of the world devils in order to rid herself of her abusive family.


This manga contains examples of:

  • Abusive Parents: Not quite her parents, but Azuma's aunt and uncle serve as her legal guardians. Her uncle repeatedly rapes her and her aunt, jealous of the attention Azuma receives from her uncle, berates and hits her. Azuma is quite small, possibly due to malnourishment.
  • The Ace: Utou is this in real life as a manga editor with the artistic capability for the big leagues. Azuma is this in Wonderland, being considered the single deadliest Alice of the entire cast.
  • Ambiguous Disorder: Most of the characters.
    • Azuma is shown to lack empathy to some extent and put herself before others.
    • Kuroe is obsessed with sex and desperate for male attention to the point of her being a threat to others while in Wonderland.
    • Peró appears to lack empathy. As a small child, he killed a cat because he wanted to see it from the inside. He attempts to kill Azuma because he wants to be the only anomaly.
    • Advertisement:
    • Saeki is dependent on others. She clings to her friend and roommate, Mika, who does everything for her. After Mika's death, she breaks down and appears willing to accept death by the fourth world devil. When Utou is kind to her, she instantly obsesses over him.
  • Ambiguously Human: The King of Maze, who is in essence the embodiment of all of Maze's darkness as an emotion. Not only does he wear an Expressive Mask that dehumanizes himself, but after Azuma chops off his head, we see another individual putting on the same mask - only to learn that he's turned the entire planet's population into reserve tanks as a method of Resurrective Immortality. As a result, he literally cannot die As Long as There is Evil.
  • An Axe to Grind: Azuma's signature weapon.
  • Anti-Hero: Azuma's not exactly the most heroic character given her.. issues. She's still a hero by definition, but comes into conflict with the rest of the cast repeatedly. By the end of the story, she trudges straight into Nominal Hero territory when she cheerfully heads off to destroy Maze to preserve what she cares about without hesitation.
  • Art Evolution: Artwork starts out rough, but chapter-by-chapter the art style steadily improves. By the end you'll be wondering if it's even the same series due to the sheer quality difference.
  • Artificial Human: Seki Hijiri, a false alias for an entity reborn from the budgie bird Bunchou-chan. By being brought into the Wonderland by accident as a corpse and essentially being a Manifestation focus for Azuma, he was given the opportunity to be reborn as a Winged Humanoid.
  • Attack of the 50-Foot Whatever: The world devils vary greatly in size and appearance, but some are massive.
  • Ax-Crazy: Peró at first, but then the King of Maze outshines him to ludicrous levels.
  • Back from the Dead: Utou, by using the logic of a Servant Devil and his proximity in a Wonderland battle he died just as he was entering. It gets doubled later on when his love with Saeki allows her to actually give him a full-on living body again like what Azuma did to produce Seki.
  • The Bad Guy Wins: The King of Maze gets exactly what he wanted: to be the only thing left in the neverending darkness, perpetually floating in the abyss of the erased Wonderland with no idea if he'll even age, expire by other means or the like. Thankfully this is inconsequential to everyone else at this point.
  • Bittersweet Ending: The planet of Maze is completely destroyed alongside Wonderland, both by Azuma, ending the World Devils, but also wiping out the Cheshire Devils that were left, and every single inhabitant, innocent or not, of the world altogether. The world of Zera continues on, the remaining cast members of the heroes persist as True Companions, Kuroe has a daughter named after Lukyon, and Azuma finally reunites with her mother - only to end up leaving her mother years later anyway for reasons the characters don't really describe in detail.
  • Black and Gray Morality: The Alices and Cheshire Devils versus the World Devils at first, though things get muddied soon enough. It dips right back to this when the King of Maze finally makes his debut, effectively creating a threat that tears apart everyone's expectations of mounting faction conflict in his attempts to Kill 'Em All just for the sake of fun.
  • Break Them by Talking: The King of Maze loves this trope, constantly breaking out into a Rant-Inducing Slight or a large, impassioned and potentially multi-page Hannibal Lecture to try to drive his enemies over to the Despair Event Horizon. While this initially works on Seki, in Azuma and Adachi's cases they both promptly attack him mid-sentence.
  • Broken Bird: Almost every main cast member is this in some way or another, but Azuma takes the cake.
  • Bury Your Gays:
    • Saeki and her roommate, Mika, speak of marriage and children. When Saeki kills the second world devil, Mika dies.
    • Ookura kills a world devil knowing his implied lover, Yamaguchi, would die. Shortly after, he dies protecting Saeki and Utou.
  • Butt-Monkey: Adachi, the poor bastard that gets brutally maimed in each battle he participates in. He's also the first to spend a "reserve tank" in defeating a World Devil, killing his mother as a result. Thankfully, he actually evolves into an Iron Butt Monkey by the final battle, as the sheer threat to children the King of Maze causes awakens his Manifestation that happens to be from Maze energy gathered from all of his injuries.
  • Cast from Hit Points: How the Alices' avatars work with every single action in Wonderland. A base of 1000 points, variable actions are usually small but big expenditures with manifesting items and weapons can take upwards to 100 or more potentially, and they regenerate one point a second. Manifestation instead works as an ongoing drain on this energy supply for great power. Killing a World Devil, however, expends all of your energy simultaneously - and the Chesire Devil keeps the Alice alive by calling on a "reserve tank", killing someone close to the Alice as a result.
  • Character Development: The main cast go through amounts of this thanks to their interactions with one another, but the character that stands out the most is Azuma. Not because of development, but rather her lack of it, only coming to understand the wishes of her allies and wanting to care for those close to her; by the time she has to destroy all of Maze to save her world, Seki is absolutely horrified when Azuma cheerfully accepts it and realizes she doesn't actually value the lives of an entire civilization at all despite everything she went through..
  • Chekhov's Gun: An early weapon attempt by Azuma is an Anti-Proton Bomb, but not having fully read the book she just previously stole, she can't actually create it so it's just an aside note. It continues to pop up occasionally throughout the series. Then she actually manages to make one in the final battle, and promptly destroys the Wonderland, ending the war.
  • The Chosen One: In a roundabout way, as Azuma is "unique" compared to the entire rest of the cast. Even when several more Anomalies show up that supposedly are the best of the best as well as handpicked for their willingness to sacrifice their reserve tanks, Azuma is coined as the "World's Destroyer", the person perfectly fit for destroying Maze to save Zera and the single strongest Alice of the entire cast, because her Lack of Empathy makes her so absurdly strong.
  • Cool Big Bro: Lord knows Adachi tries, serving as one of the few emotional tethers for Azuma once they get to know eachother. By the epilogue it's implied that he does fulfill this role, which along with Seki's presence helped make Azuma into a much more normal individual.
  • Creepy Uncle: Taken up to eleven with Azuma's uncle. He states that he is sexually attracted to young girls and rapes Azuma.
  • Dark Action Girl:
    • Azuma's motivation to kill the world devils is to kill her family.
    • Kuroe attacks and harms several other Alices in a fit of rage. She is willing to kill Saeki in order to kill the world devil, believing it will result in the death of her unborn child.
  • Dark Is Not Evil: A central crux of power throughout the story is the emotional "darkness" within oneself. The higher this darkness, the stronger they are, though their inner inhibitions might be let loose if they don't control them. Most World Devils also emphasize this in their clothing, even when our heroes go to Maze as World Devils themselves.
  • Deconstruction: Of the standard shonen protagonist and their Determinator capability, because Azuma is nigh-suicidally determined to kill World Devils so her abusive family kicks the bucket for each kill so that she can see her real mother. The entire character arc hinges on this, to the point that actually developing proper emotions again temporarily cripples her combat capability.
  • Dramatic Irony: The Cheshire Devil was responsible for Wonderland, and their remaining leader wanted to try to use it to save the rest of his group or even get them to Zera from Maze as the latter burned at the hands of the Alices they recruited. In the end, their "World's Destroyer" they molded Azuma into did what they wanted - after she ignorantly destroyed Wonderland with the last three Cheshire Devils in it, wiping out everything they fought for in the collateral. In a way, at least one of them sees it as Laser-Guided Karma for trying to doom their former world to oblivion.
  • Driven to Suicide:
    • Giger, the only member of the World Devils that the heroes ultimately communicate with personally. She claims that part of the reason is because she can't fight anymore to begin with, but really it's coming to the realization that with the Zera Alices having been humanized in her mind, she simply can't bring herself to kill them and ends herself instead - and given that failing her mission would likely result in severe punishment if not death, she goes out on her own terms.
    • Masaki, the abusive uncle of Azuma, was already driven to the Despair Event Horizon once all of his direct family were deceased, but he finally took his own life after Azuma was rescued by Seki and completely rejected his Murder-Suicide. Unfortunately for our cast, this means Azuma's next reserve tank for the final battle actually shifted to someone she genuinely cares about.
  • The Empath: The King of Maze, who can feel the emotions of everyone that enters his domain. Being that he's Ax-Crazy, he exploits this like no tomorrow.
  • Even Evil Has Standards: One of the World Devils does not take kindly to the discovery of Servant Devils, their comrades reanimated to serve the Cheshire Devils. Of course, once you find out that all of the Devils are human Child Soldiers with digital avatars hiding their true selves, and the very first World Devil was actually the brother of the leader of the Cheshire Devils and he knew, it turns out Villain Has a Point. Though the objecting World Devil was also an Anti-Villain to be fair.
  • Evil Cannot Comprehend Good: The King of Maze, a man who embodies trying to drive people over the Despair Event Horizon, cannot even begin to comprehend Seki and Azuma despite his capability in reading their emotions and memories. Then again, it's not like these two are exactly 'good' to begin with.
  • Face–Heel Turn: Lukyon, betraying and killing most of the Cheshire Devils herself so the King of Maze will let her meet her mother again, and Eric Flow, who gets killed and converted to the King's side but really doesn't mind so long as he gets to kill more.
  • Fan Disservice: Basically everything involved with Kuroe. Her motif is Lust, so she's exposed to compromising situations and the most bared skin in the series (including uncensored breasts and near-complete nudity), but it's so extraordinarily warped so as to horrify. At one point she's nearly even raped by the constructs of a World Devil, as an attempt at an Ironic Hell.
  • Freudian Excuse: The series is rife with this, explaining why most of the cast became the way they are. Even the Big Bad gets one as he was a child chosen to feel all of the darkness and pain of Maze. The result turned him so Ax-Crazy that the value of life became negligible and he does whatever he wants for his enjoyment, not for anything else.
    • Freudian Excuse Is No Excuse: When the King attempts to lay out to Adachi that he's not such a bad guy and just doing what needs to be done for Maze, Adachi - who doesn't even know who the guy is thanks to being unconscious in every fight and missing 90% of the plot - seems like he's going to hesitate or forgive the King. Only for Adachi to promptly call bullshit and immediately realize the King of Maze was enjoying this carnage. Cue the Slasher Smile.
  • Friendly Fireproof: Alices cannot hurt one another or even themselves with their Materialization unless particularly willing it in the self-harm part, so naturally a couple characters voluntarily use what would be a Taking You with Me and come out no worse for wear. Peró circumvents this in his attempts to kill Azuma by using a knife he brought from the real world, bypassing that limitation.
  • Friend to All Children: Adachi befriends Azuma after a rocky initial meeting, enough so that he becomes one of the few people she cares about, and late in the story it's implied that he's probably the most empathetic member of the main cast behind that rough exterior.
  • Heroic Sacrifice:
    • A world devil shoots at Saeki. Utou dives in front of her, taking the shot and dying.
    • Ookura shields Saeki and Utou with his body, resulting in his death.
  • He Who Fights Monsters: The long-term morality issue for the Cheshire Devils, who ultimately abandoned morality for the sake of revenge and then gathered the most mentally unstable Alices as their star pawns for the plan while trying to disregard all wishes and circumstances - and even attempt to kill Azuma to force her to fight a battle she doesn't want to. The only reason they aren't the villains is because of how essential they are to saving the world, and the fact that the King of Maze is much, much worse.
  • Idiot Hero: By all means, Adachi is actually a fairly normal guy and not that dumb. However, his Hot-Blooded actions repeatedly get him maimed and injured, and status as a Butt-Monkey actually becomes a plot point when he's totally unaware of the larger plot and even has no idea Azuma had willingly been killing the World Devils. The cast classify him as the idiot.
  • It Can Think: By the second World Devil fight it becomes increasingly obvious that they're capable of strategy and rational thought. The fourth, fully capable of speech in her body, lays it out that a World Devil is really the avatar body of a human with the Alice in Wonderland Syndrome infiltrating the opposing world - so every "monster" our heroes kill is yet another Child Soldier in the exact same situation as themselves.
  • It's All About Me:
    • Peró's entire motivation, wanting to be one of a kind and the sole "anomaly."
    • Also the motivation for the Big Bad given that the King of Maze would sooner torch both worlds to the ground and embrace eternal darkness for himself to indulge in than ever let a peaceful solution reign or admit defeat.
    • A recurring trend in Azuma's family, as all of them are secretly selfish so as to only think about their desires. This becomes a plot point when the safety of her entire world hinges on whether she has developed the morality to move past this mindset, which would doom both worlds to extinction. She didn't, and promptly genocides Maze to save strictly and solely what she cares about. Seki admonishes himself for never realizing just how selfish and broken in morality she really was.
  • Lack of Empathy: Azuma would rather her entire adoptive family keel over dead, and doesn't share a lick of genuine empathy for anyone but those close to her or the time she got pissed at Lukyon's urge to see her mother being brutally perverted by the King of Maze. This best shows when her uncle commits suicide, as she just laughs and takes advantage of the household while his and her cousin's corpses continue to sit there, and the end of the series, where she still doesn't actually value individual human lives and thus destroys Maze without hesitation.
  • La Résistance: The Cheshire Devil is a group of children from Maze with various avatars, opposing the plan for Maze to destroy Zera for the sake of Revenge due to losing their families in persecution over the failure of Wonderland for saving Maze; they don't care if Maze is destroyed, and that includes all of its inhabitants. Consequently, the King of Maze holds them all as terrorists to be killed.
  • Lovable Sex Maniac: Subverted hard with Kuroe, to the point of a complete mental breakdown when things go pear-shaped and she realizes she's pregnant. The result is one of the most disgusting scenes in the manga, where she cuts off Ookura's dick and rips out Utou's eyes to fellatio them in her Manifestation-induced insanity.
  • Manly Gay: Ookura and Yamaguchi are muscular and very masculine.
  • Missing Mom: Azuma's mother is missing. It turns out she has been trying to contact Azuma but Azuma's uncle wouldn't allow it.
  • Moral Myopia:
    • Fighting the World Devils is already a troubling and nightmarish experience for the cast, but then they find out the World Devils are actually just the avatars of humans from Maze - a parallel world fighting to avoid being destroyed in a mutual collision with Zera, or our world. What the Alices did, was kill Child Soldiers that were conscripted as vanguards to ending Zera. Even worse, the ones leading the Alices are Cheshire Devils, children from Maze hijacking Maze's invasion plan for Revenge. One world must end, and neither side wants to be the "losers".
    • Azuma fights to kill her abusive adoptive family which is technically murder already and yet she doesn't care, but by the end, what does she have to fight for? Why, living with her mother and Seki, and the friends she made! What's that, the entire world of Maze has to be genocided to prevent her world from being destroyed? She doesn't even hesitate as Seki realizes that despite everything she'd been through, she still doesn't care about human lives, only those relating to her own.
  • My God, What Have I Done?: Occurs throughout the series, but Ookura in particular realizes that he let several of his comrades die because of sympathizing over the Wonderland Syndrome with a local kid in Iraq who would suicide bomb their base. And then he was forced to slaughter the boy's home by his superiors, including other children. He and his eventual lover Yamaguchi were so taken by grief that they took up hard drugs as a result.
  • NEET: What Peró formerly was, acknowledging his being locked up by his father as the perfect life for someone like himself. Ignoring the fact that it was to keep someone as batshit as him from harming other people.
  • Nice Guy: Ookura may be a Functional Addict and gay with his best friend, but not once does the series portray him as an asshole or even rude towards other people. Even when he's hopped up on ecstasy. He's so unfaltering in being nice that he actually gets Azuma to admit he was pretty cool in his Heroic Sacrifice and start her path towards the light.
  • Not So Different:
    • The Cheshire Devils compose Servant Devils out of the corpses of World Devils - which are, by all means, people from a different class of the same world. Although some of the Cheshire Devils try to be empathetic, in the end they're so willing to destroy their own home that they even put bomb collars on Alice's necks to kill any cowards in the final battle.
    • Read the numerous tropes involving Azuma's Lack of Empathy, and then look at the King of Maze's motivations. The two are basically fulfilling the same thing of only doing what they want, the world be damned. The key difference is that Azuma genuinely fights to save her friends and the world in the end, whereas the King wants to wipe both worlds out For the Evulz.
  • The Power of Love: A recurring motif throughout the series. Kuroe comes to realize that loving one's child should be unconditional, stabilizing her mindset when even the mirror that broke her with sexual imagery displays a wholesome family image. Saeki and Utou confide in eachother with their insecurities and even revive Utou as a result with love. Ookura can pull off absolutely outstanding feats as his love works in tandem with his darkness and shines brighter than the rest of the cast. Seki exists solely because of Azuma's naive love for his former, deceased bird self. And Azuma's love for those she learned to care about gives her the capability to tap into her own light and Take a Third Option in the final battle.
    • However, a sneaky Deconstruction occurs in the epilogue when it's implied that Saeki and Utou broke up within the five year Time Skip, showing that even for as amazing as love can be, a relationship between someone that needs to depend on others to function and a person that needs to feel heroic and needed to have a purpose isn't exactly the most stable of romance.
  • Protectorate: Seki proclaims himself the one in charge of protecting Azuma, seeing as she resurrected him to begin with. Seki eventually finds out the hard way that Azuma's really the one protecting him in terms of Wonderland.
  • Rape Is a Special Kind of Evil: Azuma's uncle, Masaki, is an absolute piece of shit that has raped her repeatedly in the past since he could only be sexually aroused by underdeveloped girls. Not only did this cause a domino effect of his wife and younger son abusing Azuma, the former out of jealousy and the latter out of following example, but despite genuinely caring for his blood family, the bastard doesn't even remotely repent and attempts a Murder-Suicide on Azuma while threatening to violate her again for running away.
  • "Shaggy Dog" Story:
    • After wanting to see her mother again for the entire series as a primary motivation, to the point that the threat of her being a reserve tank crippled Azuma's esteem, the epilogue shows that her mother was, for some nebulous reason or another, consistently incapable of actually taking care of her daughter properly, causing Azuma to run off with her friends anyway.
    • The epilogue also implies that for all of their committal to eachother to the point of losing their virginity to revive Utou, Saeki and Utou had a rough break up in the five years since the ending. At the very least it can be inferred that Saeki finally lost her absolute need of dependency.
  • Someone Has to Die: Several Alices are brought to Maze, a world parallel to our own, Zera, and the home of the world devils. When they try to leave, there aren't enough portals for all of them, so someone has to stay behind. Peró volunteers, and Scapp, the Cheshire Devil that personally befriended him, sticks with him to the end.
  • Super Mode: Manifestation. Whereas Materialization crafts weapons from one's thoughts for a set amount of energy per use, Manifestation is essentially a transformation incurred by one's "darkness" of emotions reaching a critical point and allowing for superhuman capabilities to go far beyond their normal limits - at the cost of a constant drain on their energy and the potential risk of losing their shit if they can't control it. Azuma flips this on its very head when her determination to save her friends and protect their wishes as well as finally meet her mother flips her dark emotions over into feelings of light, allowing her to produce the Anti-Proton Bomb and destroy Wonderland.
  • Surprise Pregnancy: Before the third World Devil, Kuroe realizes her latest fling gave her this. The result is an absolute mental breakdown and demanding sex out of every single man present at the next fight, and upon considering that she could use her unborn child as a reserve tank, snaps into a Manifestation of lust that endangers the entire cast. Surprisingly, the story actually confronts this afterwards, as Kuroe's eventual resolve to keep the child makes her stable again.
  • Take a Third Option: In the finale, Azuma has to choose to kill the King of Maze (an implausible task at best) and thus kill Seki as a result due to him being her reserve tank, or not fight and thus die with her entire world (and potentially both worlds due to the King of Maze going pure Kill 'Em All). Her response? Pull out an Anti-Proton Bomb, which is big enough to destroy the entire Wonderland - it effectively traps the King in a neverending abyss unable to harm anyone again, doesn't hurt her comrades due to being a Materialization, and bypasses the entire need for a reserve tank to be used.
  • Title Drop: Technically speaking, Sekai Oni means "World Devil" and is a commonly used term throughout the series. A more specific case is the fight with Giger, the first World Devil to actually speak and communicate, who outright proclaims herself to be a Sekai Oni that will destroy Zera.
  • Troubling Unchildlike Behavior: Azuma yet again stands out by being the youngest of the cast and absolutely messed up mentally, to the point that human empathy doesn't seem to properly exist for her.
  • Woobie, Destroyer of Worlds: Azuma has gone through absolute hell as a child, but isn't just a one-child-army; the Cheshire Devils coin her as the "World's Destroyer". The ending of the series highlights this in that she personally has to genocide what's left of Maze to save her own world Zera. She doesn't hesitate.
  • Worf Effect: Eric Flow and Xing Long Long are hyped up as two powerful Alices, to the point that Azuma can feel Eric's bloodlust and freaks out, and Xing didn't have a single casualty in his team and even declares himself team strategist. Xing's instantly killed by the Big Bad the moment they try to infiltrate Maze, and Eric dies shortly thereafter in a Curbstomp Battle just trying to hold him off.


How well does it match the trope?

Example of:


Media sources: