Kiwaguro no Brynhildr

Kuroha Neko, the one to be blamed for everything.

For 10 years, Murakami Ryouta has been tormented by the death of his childhood friend Kuroneko, whom he had been really close to. The guilt he feels because of her death had 2 effects on his psyche: motivates him to fulfill a childhood promise he made with her to show aliens do exist (at his 16 years of life, he's already third-ranked in school and is on fast track to become a NASA researcher), and left him with a deep inability to communicate and understand the opposite sex.

One day, a girl who looks exactly like Kuroneko appears before him. Her name is Kuroha Neko, and from then on, a story of horror, experiments, human communication and despair begins.

Kiwaguro no Brynhildr (in some places called Gokukoku no Brynhildr) is a manga by Okamoto Lynn, the creator of Elfen Lied. It keeps the science-fiction horror tone and massive gore of previous works.

Tropes used in Kiwaguro no Brynhildr include:

• Anime Hair: Kikako's hair is impossibly spiky.
• Accidental Pervert: Ryouta grabbed Kuroha's boobs once by accident.
  • Unprovoked Pervert Payback: Kana insists that Ryouta wants to molest her every single time he's around; she even does this when he carries her out of a burning house.
• And I Must Scream: Milder example with Kana who is like this due to experiments -- she can only move her fingers a bit to type on her keyboard to communicate.
• Arbitrary Skepticism: Ryouta can't believe Kuroha's powers are magical, despite believing in aliens. He tries to argue aliens can be real, but it seems to disregard the fact that even if aliens existed, the probability of them being on Earth for some reason are very, very low.
• Berserk Button: The quickest way for Ryouta to bleed isn't by seeing Kuroha's breasts or fight villains: is by saying Kazumi's breasts aren't that big as she says they are.
• Bilingual Bonus: The Harnessed is the button-like thing on the nape of magic users. Due to how things are transliterated to Katakana, it's easily possible to miss that the real transliteration is her nest (which gets written in the same way), an obvious reference to where resides the parasite inside the magic users' bodies.
• Bi The Way: Kazumi shows sexual interest towards each other member of the cast, but it is stronger towards Ryouta, much possibly because everyone else is straight and he is the only male.
• Blessed With Suck: Skadi's powers are worth nothing to her because they cause irreversible damage to her body every time they're used.
• Blood From the Mouth: If magic users don't take their pills, this is the first signal of the death waiting to happen.
• Bragging Theme Tune: Kuroha creates hers own in-universe.
• Break the Cutie: All the magic users come prebroken for your convenience. You could think that further breaking is on the menu and we wouldn't blame you for it, anyways.
• Breath Weapon: Kikako's power is to shoot energy beams from her mouth.
• Brilliant But Lazy: Kogorou refused to join institutions overseas because he simply don't wants to move too much. He already considers going to Tokyo too much work.
• But Not Too Foreign: Kazumi is half-Austrian.
• Cast from Hit Points: Skadi's powers magic powers damage her body irreversibly.
• Catch a Falling Star: Subverted. Kuroneko grabbing Ryouta's hand only leads to her falling too, and apparently kills her while he survives.
• Childhood Friend Romance: Kuroha and Ryouta, since she is Kuroneko after all.
• Cloudcuckoolander: What almost everyone thought Kuroneko was for believing the Earth has been take over by aliens.
• Cosplay Cafe: Kazumi and Ryouta visit one in Akibahara as part of their "date".
• Detached Sleeves/Opera Gloves: Part of Kuroha's school uniform.
• Distracted by the Sexy: Not even Ryouta can resist Kotori's....tracts of land.
• Does Not Know Her Own Strength: Kuroha injures Ryouta in an arm-wrestling match.
• Dreaming of Things to Come: Skadi see the future when she dreams.
• Dumb Blonde: Kotori has strawberry blonde hair, the lowest grades of the group and poor sense.
• Eldritch Abomination: The horrendous thing that remains when a magic user is destroyed with her Harnessed's down-left button gives all vibes of this. Might be an alien life form that parasites the magic users' bodies and gives them their powers, but this is unconfirmed.
• Elegant Gothic Lolita: Kana, complete with Princess Curls.
• Evil Counterpart: Valkyria looks exactly like Kuroha but with white hair and blue eyes, and has a different, sadistic personality.
• Explosive Leash: The second button on the Harness is this by default, but the organization implants a beacon on the witches they send to activate it remotely if they desire to
• Fake Memories: One of the magicians have the power to eat memories and give to her victims the memories she wants them to have.
• Fan Service: Lots and lots of it ahead.It helps that Kazumi is a Shameless Fanservice Girl that will expose the other girls if they're not willing to strip.
• Fate Worse Than Death: The third button on the Harnessed will cause something like that to magic users.
• Fundamentally Female Cast: All of the magic users shown until now are teenage girls.
• Gainax Bounce: Kotori, to such a point Kazumi even asks if her breasts are real.
• Gorn: Okamoto indulges in this each time more and more; just compare the post-accident Ryouta in episode 1 to the fight with Saori in chapter 9.
• Government Conspiracy: The reason why asking the japanese authorities for help is pointless.
• Gratuitous German: Kazumi seemed to be an in-universe example, giving herself an german surname and talking german after transferring to Ryouta's school. Then subverted when she reveals she's half-austrian.
• Harem Hero Ryouta is a justified Type 1 since he's only a Muggle, though he compensates that with his sharp mind.
• Hotter and Sexier:The anime BD versions show nipples.
• I'm Dying, Please Take My MacGuffin: Akane gives Kuroha a bag and says to her to remember she's the only one who can save the world from "ruin" before dying.
• Identical Stranger: Names and appearance are similar, but Kuroha doesn't have the moles on her armpit. And, of course, Kuroneko died when she was a child, and we only see Kuroha as a teenager. Averted later when both the audience and Ryouta discover her moles just changed places in her body as she grew.
• Hair Decorations: Kazumi wears a headband.
• Laser-Guided Amnesia: Everytime Kuroha uses her powers, she loses a part of her memory.
• Leotard of Power: Saori wears one.
• Ludicrous Gibs: Lots and lots of it.
• Mercy Kill: Kana asks for this after the house where she and Kuroha lives burns down along with the pills they need to continue to live.
• Mind Over Matter: Kuroha isn't actually super-strong like it was implicated at first: she has telekinetic powers. It is more clear in the anime than in the manga because a certain scene where Kuroha don't seems to move but things still get crushed happen first.
• More Hero Than Thou: The fact the pills are limited for the witches makes it a constant question.
• More Teeth Than the Osmond Family: The parasites that inhabit the magician's bodies.
• Mysterious Transfer Student: Kuroha's arrival sets the whole plot in motion.
• Nerds Are Virgins: Kazumi seems to have that belief, at least towards people that buy eroges.
• New Transfer Student: Kuroha Neko, that affirms to have magical powers.
• Nipple And Dimed: The manga and TV version of the anime play it straight. The BD version of the anime averts it.
• Not a Date: Kazumi really wants her and Ryouta's visit to Akibahara to be like one.
• Oblivious to Love: Ryouta fails to notice how close Kitsuka wants to get close to him.
• Person of Mass Destruction: Ryouta basically calls the trope by name when referring to Kikako, whose powers allows her to cause massive amounts of damage with an energy blast launched from the mouth.
• Photographic Memory: What makes Ryouta specially smart is his capacity to store things in his mind with uncanny precision.
• Power At A Price:
  • Kana can see the future, but is unable to move or even talk by herself.
  • Kuroneko slowly loses her memories every time she uses her powers.
• Power Incontinence: Kuroha and Kana need to eat special pills or otherwise their bodies will decay because their own powers begin to rip them apart.
• Prophecy Twist: Kana's prophecy about Kotori is just a little wrong. Kotori is smiling not because she is happy about killing the person dead in Kana's vision, but because that is her default response to a horrible, traumatic event.
• Psychic Nosebleed: Subverted, it is actually the first symptom before an horrible case of Power Incontinence begins to destroy the magician's bodies from the inside.
• Puppy Dog Eyes: Kuroha is able to use this on Ryouta just by staring at him and crying because the art style already makes her eyes big.
• Rapunzel Hair: Kotori, to the point it hides her Harness.
• Ripple-Effect-Proof Memory: Saori has this as part of her power.
• Running Gag:
  • People making comments about Kotori's weight. Even more hilarious because she is incredibly hot and don't looks fat all.
  • Ryouta talking or even thinking about Kazumi's breasts and how they aren't impressive. And then Kazumi hitting him.
• Scary Teeth: Kikako has sharp,shark-like teeth.
• Scry vs. Scry: Though it's more like Kana's group vs Skadi, since Kana isn't all that smart.
• Secretly Dying: Kazumi is out of pills and slowly dying when our main protagonists contact her. That's the reason why she accepts to help them despite they having no pills: she still wants to help someone before she dies.
• Seers:
  • Kana is one.
  • Skadi is one, to an scarily accurate level. Her predictions apparently are always 100% right and can't change.
• Self-Fulfilling Prophecy: Averted. Predictions of the future change if the people involved change their behaviour by being informed of a prophecy.
• Set Right What Once Was Wrong:
  • Kana's powers allow that to happen if she informs someone that can alter it of it.
  • Saori's power to turn back time also allows it, though she can't revert the consumption of magic of using this power.
• Shameless Fanservice Girl:
  • Kazumi tempts and then makes Ryouta sees her bare breasts without a care in the world. Hell, her whole behaviour seems to revolve around sexual topics.
  • Nanami's way of attracting attention is by lifting her skirt. it is an effective method but it seems...suspicious. Then she strips in public to attract attention when Kurofuku tells her she can't lift her skirt.
• Skinship Grope: Oh Kazumi, you're such a naughty girl towards your female friends...
• Spoiler Opening: The manga begins with Kuroha bleeding on the floor and Ryouta stabbing her, screaming "If only you didn't exist.. If only you have stayed dead!". All of this in a desolated and annihilated landscape, with the shadow of a girl watching the scene the only extra detail. Knowing the author, this can't possibly end well.
• Squishy Wizard: All magical users seem to have normal, fragile human bodies.
• Straw Misogynist: Kogorou affirms he isn't married because he thinks women are stupid...towards a bunch of young girls. No wonder why his sister seems to dislike him.
• Suspiciously Specific Denial: Kuroha makes a song about how indirect kisses don't matter at all.
• Sweet Tooth: Nanami does allege she needs sugar for her powers though.
• Take My Hand: Kuroneko grabs Ryouta's hand when he falls off a ledge in the beginning of the manga. It don't works like intended and both kids fall off dozens of meters.
• Tall, Dark and Bishoujo: Kuroha has traces of this (she only lacks the tall part a bit).
• Techno Babble: Ryouta's explanation of RSA^[1] leaves a lot to be desired.
• Technopath: Kazumi's magical power is to...operate electronic machines with her mind.
• Teleporters and Transporters: Kotori has that power, allowing her to change places with another person, but immediately drains her of all her magic.
• The Ace: At least intellectually. Ryouta is the best student in his school and third-best in Japan.
• The Conspiracy: The main villains are of this kind.
• The Dreaded: Kikako is an AA+ magician who sets the other magicians in fear just by hearing her name.
• The Masquerade: Enforced to such a point that heroes can benefit from it because the mysterious organization that creates magicians don't would dare to make a move who could risk the masquerade's existence.
• The Needs of the Many: Kuroha says to Ryouta to not leave the observatory after he decides to not miss the bus because if he did ride the bus, a lot of more people would die from a failing boulder that if he just walked to his destiny.
• The Quiet One: Kikao don't talks a lot.
• Time Master: Saori's second power is to revert time back for one minute.
• The Omniscient Council of Vagueness: The organization behind the magicians is leaded by one.
• Transfer Student Uniforms:
  • Because Kuroha never attended school, she wears a self-made uniform (see page image).
  • Kazumi's uniform consists of clothes she found at the abandoned village.
• Truth in Television: In chapter 6, it's revealed that Kazumi's magic is her capability to factor very large integers with ease, and that makes her capable of breaking security of many systems. Then again, the explanation and theory exposed in the chapter would make mathematicians and cryptographers cringe.
• Undead Tax Exemption: Kuroha can only attend school because she knows a very skillful hacker.
• Unskilled but Strong: Kikako isn't very smart and her attack is very straightforward, but the power of that one attack is incredibly destructive.
• Yaoi Fangirl: Yuki's web history leaves little to deduce.
• You Are Number Six: The organization refers to magic users by number rather than name.
• You Gotta Have Blue Hair:
  • Kuroha's hair is either dark blue or Shiny Midnight Black while Ryouta's hair is light green.
  • Kazumi's hair is pink in the anime.
• You Have Outlived Your Usefulness:
  • Happens with several magicians once the organization no longer needs them.
  • Kurofuku is shot after he fails to retrieve Kotori using Skadi's power.
• Zettai Ryouiki: Kuroha wears thigh-high black stockings to a short dress as her school uniform. Class B.

1. ↑ the de-facto example of real-life asymmetric Encryption