Characters / Future Diary: Yuno Gasai

Future Diary Main Character Index
Diary Holders (Yuno Gasai) | Supporting Characters | Another World

WARNING: Unmarked Spoilers ahead!

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Yuno Gasai - The Second

Voiced by: Tomosa Murata (JP), Brina Palencia (EN)

An insane, violent, sociopathic, nihilistic classmate of Yuki's who's obsessively stalking him, claiming to be madly in love with him. Her "Yukiteru Diary" tells her what's happening to Yuki at every 10-minute interval, and won't show anything unrelated to him except for her own dead end. Since Yuki's diary records everything except what happens to him, the two of them presumably make a formidable team. If only she was more comforting to be around...

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A-E

• Abduction Is Love: Yuno drugs and kidnaps Yuki to protect him until July 28th, chaining him to a chair. Yuki eventually breaks free thanks to his friends, and abandons Yuno. It doesn't last though.
• Abhorrent Admirer: While Yuno is a very pretty girl, Yuki is initially put off by the fact that she's an insane and creepy stalker. For most of their relationship, Yuki is too scared to get close to her because of her unpredictable behavior until he does eventually reciprocate her feelings.
• Absurdly Sharp Blade: Yuno is typically armed with a variety of kitchen implements, but the damage she does with them is out of this world.
• Accidental Murder:
  • When Yuno finally got fed up of Saika's abuse, she locked Saika and Ushio in the same cage Saika locked her, hoping they would realize how she felt and change back to their old selves. They didn't, and eventually died of hunger.
  • She also did this with 1st-world Yuki, in a sense. She backed out of their Suicide Pact, thinking that she could bring him back to life after becoming God. However, it turns out that she can't, making her unintentionally responsible for his death as well.
• Action Girlfriend: Almost immediately after stumbling into The Game, Yukiteru encounters Yuno who makes it her top priority to protect him from harm and is the one who does most of the fighting in the beginning. The only thing that stops her from being a straight example is the fact that she's a psychotic Yandere.
• Aggressive Submissive: She's very direct and aggressive towards Yukiteru, but when she finally "becomes one" with him she becomes super-shy.
• The All-Solving Hammer: Yuno often resorts to pulling out her knife to deal with troubling situations.
• All Take and No Give: The true nature of her relationship with Yuki. Yuki uses Yuno as a guard whilst Yuno uses Yuki as emotional support. Eventually Yuno acknowledges this and tries to convince herself and Yuki that their love has been fake, and they have been merely using one another, in the hope that he gives up on her and she can kill him to go back in time without regrets. When that doesn't work, she traps him in a Lotus-Eater Machine where she doesn't exist but otherwise Yuki has everything he ever hoped for. He manages to break free, apparently because their love started out fake but became something deeper over time.
• Alternate Self: The Yuno who's crazy for Yuki is from the first timeline, who jumped to the second timeline after becoming a god and killed 2nd-World Yuno to take her place. She commits suicide to let Yukiteru become Deus' successor, and Murmur saves a copy of her memories which she gives to 3rd-World Yuno, who that timeline's Deus chooses as his successor so she can be together with him.
• Always Save The Boy: The only person Yuno cares about is Yuki and she will do anything to protect him. Anyone else can just die.
• Anti-Villain: The Woobie variety. Yuno certainly is a batshit crazy Yandere, but she can come off as sympathetic due to her past and the circumstances she must face in the series. However, many of her actions go beyond justifiable and make it hard to actually sympathize with her up until perhaps her Heel Realization and suicide at the end.
• Attention Whore: Yuno's obsessed with getting Yuki's attention and gets fiercely jealous whenever Yuki interacts with ANYONE else and due to her paranoia, she thinks that Yuki will leave her and focus on someone else.
• Attractiveness Isolation: In her backstory in the anime. The manga on the other hand averts this; it is shown that before the main story started several of her schoolmates tried to ask her out, but she turned them all down.
• Ax-Crazy: Subverted. The series absolutely wants you to think that Yuno is an example of this trope, but as her backstory and true motivation gets revealed, she becomes a little more... complicated.
• Badass Adorable: She's beautiful, adorably Moe, extremely in love with Yukiteru and incredibly skilled in combat.
• Badass in Distress: During her fight against Sixth, Yuno is taken captive by Tsubaki.
• Badass Long Robe: During the final battle, she wears a black robe.
• The Baroness: She's definitely got the Sexpot type appearance and age but has the fear factor of the Rosa Klebb type. She's young and attractive, and yearns for Yukiteru. Yuki himself though is downright terrified of her, but she kills herself to let Yuki live.
• Battle Couple: She and Yuki develop into this. As their relationship grows and Yuki becomes more competent in combat, they work together to take down their enemies.
• Because You Were Nice to Me: Yuno's devotion to Yukiteru stems from him jokingly making a marriage proposal to her right after she killed her parents, spurring her into devoting her future to him.
• Being Tortured Makes You Evil: She was locked in a cage and starved by her mother, which caused her to lose her mind.
• Big Bad Friend: In the last few chapters, Yuno becomes Yukiteru's final enemy after he refuses to kill her and he discovers she is actually the Yuno from an Alternate Timeline.
• Body Backup Drive: After being Driven to Suicide, Mur Mur and Deus from the 3rd-world implant first Yuno's memories into her still-living 3rd-world self's mind so she can become god and save Yukiteru.
• Bodyguard Crush: Yuki uses Yuno as his bodyguard during the Survival Game, while Yuno is glad to use this as an excuse to be with him all the time.
• Break His Heart to Save Him: Sort of. When she finds that she can't bring herself to kill 2nd-world Yuki, she desperately tries to make him hate her, even claiming that they never really loved each other, so that he will accept the Lotus-Eater Machine she prepares for him. However, while she does do this to keep him alive, it isn't especially noble since she was the one trying to kill him so that she could repeat the game with his 3rd-world incarnation (which she still plans on doing). Then again, she ultimately doesn't go through with it, and kills herself so that he can win the game and live.
• Broken Ace: She's smart, beautiful, diligent, and an extremely dangerous Ax-Crazy Yandere.
• Broken Bird: Yuno is incredibly broken from severe parental abuse, accidentally killing her parents, going through the survival game once before, losing the only person that gave her a reason to live (1st-world Yukiteru), finding out the hard way that not even Deus's powers can bring the dead back to life, and having to go through it all again, murdering her younger 2nd-world self in order to take her place.
• Cassandra Truth: When Yuki refuses to listen to her warnings about Tsubaki and her followers.
• Charles Atlas Superpower: In the manga at least, by the time of the last fight with Eleventh in the 2nd-world her fighting experience made her strong enough to cut grown men (in this case Eleventh's mooks) in half with a sword. In one case she is shown cutting a man in half while holding her sword with one hand.
• Clingy Jealous Girl: She won't let anyone, male or female, get close to her beloved Yuki. Yuki's mother is a notable lucky one, since she was nice to Yuno and approved of their relationship.
• Clothing Damage: When Tsubaki orders her followers to strip and gang-rape Yuno.
• Cloudcuckoolander: Due to how crazy and unpredictable she is, her sense of reality is rather unbalanced and skewed in an extreme way.
• The Corrupter: For Yuki, especially when her influence gradually made him as bad as the other players.
• Creepy Child: A 14 year old girl who appears cute and childish on the surface, but is actually extremely murderous and more intelligent than she lets on.
• Creepy Monotone: In the English dub, she's prone to speaking in monotone in her creepy moments.
• Crippling Overspecialization: Her Diary only gives information on what's going to happen to Yukiteru (apart from Yuno's DEAD END). That makes it a nearly-useless tool for making tactical decisions on its own, only becoming useful when paired with Yukiteru's Diary.
• Curtains Match the Window: Pink hair and eyes.
• Custom Uniform: A weird case of the main teens, only she bothers to wear the school uniform. It's part of her model student facade. The reason one can be sure that it's the school uniform is that many are seen wearing it in the epilogue.
• Cute and Psycho: Her normal appearance, high pitch voice, and "cute" mannerisms only help underline how nuts she is when she snaps and makes her even creepier.
• Cute Bruiser: How she can lop off body part after body part with just kitchen cutlery is anyone's guess.
• Dark Action Girl: She's one of the strongest fighters in the game and also a terrifying psychopath.
• Death Seeker: Not outright stated, but Yuno heavily implies that she wants to die in order to ensure Yukiteru wins the game in the 2nd-world, rather than win it herself and repeat the whole scenario a third time. She only tries to kill him when he absolutely refuses to take her life, and she decides to repeat the game in the 3rd-world for another shot at setting him up to win while spending more time with him again. And even then, when Yukiteru told her to just stab him and be the winner of the 2nd-world's game, she decides to just kill herself anyway.
• Declaration of Protection: She swears to protect Yukiteru at any cost.
• Deconstructed Character Archetype: Even though Yuno is a Trope Codifier of the Yandere archetype in anime/manga, a significant turning point in her Character Development is when she realizes this in Chapter 57 and admits to Yuki that their relationship was one of convenience; she needed someone who would never (could never) abandon her, and he needed someone to protect him. Their current relationship only works because she's extremely screwed up, and her acknowledgement of this makes Yuno a thorough example of this character archetype. The archetype itself is never reconstructed, but her mental health improves and eventually she and Yuki get into an actual relationship not based on fear as both recognize their mutual romantic feelings have become genuine no matter how messed up both of them are by the end.
  Yuno: Both of us were only using each other. […] You were using me to survive, and I was content with letting myself be used. […] I would have been fine with anyone as long as I could emotionally depend on them. And you were fine with anyone as long as he or she could protect you.
• Deity of Human Origin: She already became god by winning the Survival Game in the 1st-world.
• Despair Event Horizon: After backing out of her and 1st-world Yuki's Suicide Pact, thereby winning the game, she discovers that she can't bring him back to life, sending her completely over the edge to become the psychotic Yandere we've known throughout the series.
• Deuteragonist: She's the second protagonist.
• Devoted to You: Once he truly falls in love with her, Yukiteru will do anything for Yuno and she becomes the person most important to him after his parents die. He even rejects his ideal world with both of his parents alive and together because he can't be happy in a world without Yuno. After her death, Yukiteru spends 10,000 years mourning Yuno's death, without even bothering to try and create a new world with his God powers.
• Died in Your Arms Tonight: Yuno dies in Yuki's arms after she stabs herself.
• Dissonant Serenity: She's famous for this. She can do the worst things while wearing the brightest smile on her face.
• The Dog Bites Back: Saika's abuse made Yuno snap and she (unintentionally) killed Saika and Ushio.
• Dull Eyes of Unhappiness: In Episode 11, when she and Yuki are taken into the police station for questioning her eyes go dull when she decides to try to find a weapon.
• Easily Forgiven: She does a lot of things that should be unforgivable, such as trying to kill innocent people, kidnapping Yuki, manipulating him into killing his friends, and generally being a danger to everyone around her. Yuki, for the most part, seems to realize how crazy she is, but for some reason, always forgives her.
• Elevator Snare: In their first meeting in the series, Yuno forces her way into an elevator, corners the terrified Yuki, and then gives him his First Kiss. Cue the Uncomfortable Elevator Moment, at least for Yuki.
• Engaging Conversation: In the backstory, Yuno, after a bit of dialogue with Yuki, states that she wants to become his bride. He brushes it off and jokingly accepts, believing she was only kidding. She wasn't.
• Evil Laugh: She can't help herself from this after she successfully manipulates Yuki into killing Hinata.
• Evil Orphan: Played With. Yuno is an orphan and directly responsible for the death of her adoptive parents, but it only turned out that way because their neglect and abuse caused her to snap and kill them by accident. When she travels back in time, Yuno herself is shocked to see how much of a Heartwarming Orphan her past self is and becomes disgusted with how evil she has become after forgetting she did believe she could be happy with her adoptive parents.
• Evil Sounds Deep: Much like B.B. Hood/Bulleta, Yuno goes from squeaky and adorable to guttural and menacing whenever she's incredibly pissed.

F-N

• Face of an Angel, Mind of a Demon: She's got the looks of an angel, sure; but for the sake of her beloved Yuki, she thinks like everyone else is nothing but dead weight.
• Fanservice Pack: Yuno went from having an appropriately-sized chest for a middle schooler (fairly small in the beginning) to having large breasts in the course of about two chapters.
• Faux Affably Evil: At school she's seen as a School Idol and is very nice to everyone around her. But when you get to know her, you realize how messed up she is.
• Feminine Women Can Cook: Uses it to impress Yukiteru's mother. How feminine she is is up for debate though, considering her fallback plan if that didn't work was to use her "tools".
• First-Name Basis: The fact that she refers to Yukiteru by a diminutive form of his first name demonstrates just how affectionate she is toward him. Prior to her feelings becoming so intense, she referred to him in the normal Japanese manner by using only his surname. This becomes a huge plot point later, after we learn that she has two diaries, because each diary refers to him by one of those names respectively. This is because the Yuno we know went back in time, killed the Yuno from this timeline before she switched to calling Yukiteru by his pet name, and kept her diary.
• For the Evulz: Most of the time, she kills to protect Yuki or keep others away from him, but some of her killings make it look like she just commits them for the hell of it.
• Forceful Kiss: Steals Yukiteru's First Kiss during their first meeting in the series.
• Freudian Excuse: Her mother Saika abused her, going as far as to lock her in a cage where she left Yuno to starve. This made Yuno snap and she ended unintentionally killing her parents by leaving them to starve at her cage. She became obsessed with Yuki because when he accepted her marriage proposal he gave her a new reason to live. Then she had to go through the Survival Game and she lost the 1st-world Yuki. All this made her into the crazy Yandere we know.
• Genki Girl: It's fair to say that Yuno gets VERY enthusiastic anytime Yuki pays her any attention.
• Girl with Psycho Weapon: Though, unlike other Yanderes, she doesn't seem to have an iconic weapon. She is most commonly portrayed with the axe that she wields in the battle against the Sixth, though.
• Girly Bruiser: A cute girl with waist-length Girlish Pigtails(that are pink, no less), an overly bubbly, romantic, and affectionate demeanor around her crush, who mostly wears dresses, particularly a Sailor Fuku, and is skilled at making home-cooked meals. She is also a psychopathic Yandere with proficient fighting and axe-swinging skills, the God of the First World, and capable of slaughtering even trained police officers who threaten Yuki with whatever weapon she can get her hands on.
• Girlish Pigtails: Subverted. They make her seem cute and innocent at first, but she quickly shows her true colours as a murderous Yandere.
• Glowing Eyes of Doom: Her eyes sometimes appear like this.
• God Is Dead: She had already become a god in the 1st-world, but dies by committing suicide to ensure Yuki lives.
• God Was My Copilot: For Yuki. Unlike most cases of this trope, an evil influence. However, she has little power in this world.
• Good Girl Gone Bad: Long ago, Yuno was a really good little girl, until her adoptive mother began to abuse her and keep her in a cage for not living up to her expectations. And then Yuno went bad after (unintentionally) killing both her parents. And it just went downhill from there.
• Go Out with a Smile: She dies smiling at Yuki as she remarks that he had gotten so much better at kissing, happy that Yuki gave her a place to belong.
• Go Through Me: Yuno is more than willing to put herself on the line to protect Yuki.
• Green-Eyed Monster: She already showed signs of this before the games began. It's very evident that she's jealous of Yuki's friends and even though they don't need to die to complete the game she tricks Yuki into killing them all and beheads Akise herself.
• Guile Heroine: Has an impressive bout against the Twelfth by taking advantage of his heightened sense of hearing.
• Heel Realization: She realizes just how warped she's become once she sees her family in the 3rd-world come together again to protect her younger self. However, she believes herself to be too far gone for redemption and makes a suicidal move to try to kill them all with the threat of Kurusu shooting her dead. She eventually settles on stabbing herself and letting Yukiteru live instead.
• Heroic Suicide: In the end, when Yuki asks her to kill him so she can become god again, Yuno fatally stabs herself so Yuki can live.
• Hot Goddess: She's the one who became God in the 1st-world and also quite attractive.
• Hyper-Awareness: She became suspicious that her and Yuki's food was poisoned... by feeling that the cherry tomatoes were slightly heavier than they were before they had been washed... while balancing one on her fork.
• Hypercompetent Sidekick: She has much more experience in the Diary Game than Yukiteru does and she does most of the fighting.
• I Just Want to Be Loved: All Yuno ever wanted was for someone to love her, but she had forgotten about it until she meets her own past self and remembers how much she wished her Abusive Parents to become a loving family. In the end, Yuki proves to Yuno that he loves her enough to be willing to die for her and Yuno kills herself to let him live since she already got all the love she ever wanted from him.
• I'll Kill You!: "ARU AKISE, YOU WILL DIE HERE AND NOW!"
• Image Song: "Red Love" for her Yandere self and "Happy Love" for her normal self.
• Indifferent Beauty: Yuno is aware of how popular she is at school, but she doesn't care.
• In Love with Love: At first, she just acts like she loves Yuki because him jokingly accepting her marriage proposal was the only thing that gave her hope for the future. She even admits that she would have been fine with anyone as long as she could emotionally depend on them. However, she ultimately realizes she has come to genuinely love Yuki despite her attempts at convincing herself that her love was all an act.
• Interrupted Suicide: She actually tries to kill herself seconds before her death, provoking the 3rd-world Kurusu into firing a bullet at her. Mur Mur saves her.
• It's All About Me: For most of the series, Yuno's motivation isn't "protect Yuki", it's "make sure me and Yuki end up together".
• Jerk with a Heart of Gold: Yuno is an extremely violent, selfish and manipulative psychopath who impulsively kills others without a second thought but she does genuinely love Yuki and will risk anything to protect him.
• Jumping Off the Slippery Slope: While Yuno always had an obsessive desire to protect Yuki, she was initially able to keep her Ax-Crazy tendencies in check. It was actually Yuno who convinced Yuki to seek out his classmates for help when Minene was bombing their school. But after they capture him and try to hand him over to Minene, this causes Yuno to snap in lose any faith of trusting any outside parties.
• Katanas Are Just Better: She is apparently skilled at kendo, as she wields a katana to devastating affect during one arc.
• Kill and Replace: She killed her 2nd-world self to take her place and meet Yuki again in the new timeline.
• Killing Your Alternate Self: The Yuno seen for most of the series was originally from an Alternate Timeline. After her world's Yuki died and she became god, she went back in time to kill the second timeline's version of herself and replace her.
• Kubrick Stare: After Yuki discovers the room in her house that contains the corpses of her parents and her 2nd-world self, Yuno gives Yuki a seriously terrifying glare through his letterbox - while wishing him a good night.
• Lack of Empathy: To everyone other than Yukiteru. When Tsubaki told her that she was going to destroy the world after becoming god Yuno's only gripe with that was that it would also kill Yukiteru. Late in the series she outright states that she doesn't care how many more people she'll kill in the future, because they are all useless pawns and because they'll be revived anyway after she goes back in time again (ignoring the fact that technically they would be different people).
• Lady Macbeth: She usually encourages Yuki to brutally murder their opponents without hesitation and until he resolves to do it, she does all the dirty work.
• Large Ham: Due to how crazy, unpredictable and manic Yuno can be with her various mad antics.
• Last Kiss: Before dying, Yuno asks Yuki to kiss her one last time.
• Little Miss Almighty: She's only 14 years old and she already became the god of the 1st-world.
• Long Hair Is Feminine: Her pretty pink hair is down to her waist.
• Longing Look: Her intoxicated expression as she promises to "protect" Yuki, also known as the "Yandere Trance", which has since reached Memetic Mutation status.
• Love Makes You Crazy: Or was she already crazy to begin with?
• Love Makes You Evil: At times, the lengths at which she goes to show her admiration comes across as something that can only be thought of by a monster.
• Love Redeems: It takes a lot of deaths, but eventually with Yuki's help Yuno eventually overcomes her psychotic tendencies and even sacrifices herself to make him the new god out of genuine love for him.
• Mad God: Besides being a psycho Yandere, she was the one who became a god in the 1st-world. However, this doesn't apply to her 3rd-world self since she looks mentally stable before and after becoming a god.
• Mad Love: With Yukiteru. Her psychotic obsession, extreme Clingy Jealous Girl behavior, and homicidal tendencies make him want to stay the hell away from her at the beginning, although Yuno would never let him do that. On the other hand, her combat skills and murderous devotion to him make her a reliable bodyguard, and Yuno even says she doesn't care if Yuki is only using her for his protection as long as he stays with her.
• The Man in Front of the Man: Yuki is being manipulated by her and not the other way around.
• Manic Pixie Dream Girl: Yuno is a manic and eccentric girl who falls for gloomy loner Yuki and all she wants to do is guide him with the survival game designed by in her own crazy and chaotic way.
• Manipulative Bitch: Throughout the series, especially her Batman Gambit in Episode 22. Although it must be stressed that this only applies to the Yuno that is present for most of the series: the 1st World's Yuno. As we see, Yuno before Deus' game and Yuno when Deus' game never happened is not nearly as efficient.
• Masculine Girl, Feminine Boy: Masculine Girl to Yuki's Feminine Boy. Yuno is an aggressive and violent Yandere while Yuki is a meek and timid wallflower and for the most part of the series, Yuno is often the one to protect him and look after him.
• Mask of Sanity: She pretends to be a normal, innocent girl, when she's actually an Ax-Crazy sociopath. It's surprisingly subverted by the end of the series, where we learn that beneath the Ax-Crazy sociopath is a normal, formerly innocent girl who simply broke.
• Memory Gambit: She allows Murmur to seal away her memories of the first world to avoid drawing the attention of Deus.
• The Mentally Disturbed: The series initially paints her as a typical Yandere, but slowly starts pulling the curtain away and revealing that her situation is much more complicated than it first seems: she essentially has horrific PTSD from being tortured by her parents and then accidentally permanently killing Yuki in the first run. Her actions are half from trauma and half from guilt.
• Mood-Swinger: She often shifts between lovesick, psychotic, and in rare occurrences, cold and emotionless.
• Ms. Fanservice: Throughout the whole series.
  • Early on, she and Yuki visit a pool where Yuno loses her swimsuit.
  • Later on, Yuno chains Yuki to a chair. This requires her to attend to all his, ahem, "duties". And on top of all that, she spends the entire time in nothing but a bra and panties.
• Murder Is the Best Solution: Murder is her preferred way to deal with problems.
• Murder the Hypotenuse: In her own words "Everyone who comes between me and Yuki can just die!" Probably comes with the whole Yandere thing.
• My God, What Have I Done?: Has a major one after being rebuked by her past self in the 3rd-world. Yuno actually starts shaking once she realizes how much she had changed when she lost all of her hope for the future, and seriously looks frightened at what she's become.
• No Sense of Personal Space: Yuno will take any chance she gets to hug and kiss Yuki.
• Nominal Hero: She might as well be this considering she's Ax-Crazy and is only on the "good" side because of Yuki
• Not Good with Rejection: She doesn't take well Yuki rejecting her at all.
• Nothing Nice About Sugar and Spice: Despite her outwardly feminine demeanor, she is evil, murderous, and obsessive.

O-Y

• Obfuscating Stupidity: Though there were earlier hints, Fridge Logic tells you she has been displaying this the entire story. We find out she has played the survival game through before, so either she pretends not to know, or has repressed it completely.
• Official Couple: With Yuki. It starts off with Yuno as the obsessed stalker that Yuki calls his girlfriend to keep her under control, but their love eventually grows into something more genuine and they become a true couple.
• Offscreen Teleportation: She can appear out of nowhere.
• Omnicidal Maniac: If they aren't Yuki, she doesn't care what happens to them and will kill anyone who gets in her way. She is responsible for the destruction of the 1st-world since she abandoned it after becoming its god in favor of replaying the survival game again.
• Only Friend: She considers herself the only friend Yuki needs. She's perfectly fine with killing anything or anyone who may take his attention away from her.
• Opposites Attract: Yuki being a meek and timid introvert and Yuno being a reckless and aggressive sociopath, these 2 become something of an Odd Couple which progressed from Yuno's Yandere tendencies as she stalks him relentlessly and Yuki is a pushover that depends on her for survival.
• Palm on Cheek Pose: Does this as she promises to "protect" Yuki. This example is popular for not being cute, but creepy instead - in fact this leads to an internet meme called "Ecstatic Yandere Pose".
• Pants-Free: Yuno seems especially fond of this when there is an unconscious Yuki around.
• Parental Neglect: Her adoptive father would work late hours and fail to notice her mother's escalating abuse.
• Pink Means Feminine: Has long pink hair tied in pigtails, with pink eyes to match, although it overlaps with Psycho Pink below.
• Pitbull Dates Puppy: Yuno is a psychotic, violent and possessive Yandere and she usually forces her affections on the Extreme Doormat Yuki. Taken to an extreme when she kidnaps him, ties him to a chair and keeps him drugged for an entire week, to ensure that he'd stay "safe".
• Pre-Insanity Reveal: A flashback to one year prior to the start of the series shows that while Yuno was a hyper-jealous Stalker with a Crush, she wasn't as much of a deranged Yandere as she is now. The worst she tried to do when Yuki had a crush on another girl was attempting to ruin his Love Confession. Compare that to the Yuno we're familiar with murdering anyone who gets between her and Yuki without remorse. This is because the current Yuno already went through the Survival Game once in an Alternate Timeline, which explains where her homicidal tendencies and incessant paranoia came from.
• Properly Paranoid: Zigzagged. She's extremely suspicious of the people around her, and has no problem killing innocent people on the off-chance that they may threaten her relationship with Yuki, and she even drugs and restrains Yuki for a week to keep him "safe". However, her paranoia has repeatedly turned out to be spot-on in the Survival Game, such as suspecting the sixth of being a Manipulative Bitch (she was), refusing to eat cherry tomatoes because they were slightly heavier than they were before being washed (the fifth had injected poison into them), and assuming that one of Yuki's new friends was collaborating with whoever sent the dogs after them (Hinata and Mao were both working for the tenth).
• Property of Love: Yuno labels Yuki as her property and she won't let anyone take him away from her. Likewise, Yuno claims she belongs only to Yuki and she will let him use her for whatever he wants.
• Psycho Knife Nut: Yuno is one of the most famous and trope-defining yanderes in anime, and a knife is one of her main weapons.
• Psycho Pink: Originally appearing to be a Rose-Haired Sweetie, Yuno quickly exposes her wild side by killing anything and everything that could pose even a semblance of a threat to her relationship with Yuki in a truly impressive feat of Yandere obsession.
• Psycho Sidekick: She's Yuki's Yandere sidekick/girlfriend. Throughout the series, she kills, dismembers, schemes, manipulates and does a lot of evil stuff to people with little to no regard just because she wants to protect and be with Yuki.
• Psychopathic Womanchild: She's a very psychotic and unstable person who's prone to mental breakdowns and behaving impulsive and immature especially with her relationship with Yuki.
• Put the "Laughter" in "Slaughter": Yuno is prone to fits of maniacal laughter that show just how unhinged she is, particularly with killing things.
• "The Reason You Suck" Speech: About the relationship between her and Yuki when she finally acknowledges its true nature. While it did start off as that though, by the time she made this speech it had evolved into something more real.
• Redemption Equals Death: Once she finally realizes how far she has gone and that she can't bring herself to kill Yuki after all, she stabs herself so Yuki can become god.
• Red Eyes, Take Warning: Sports red eyes sometimes, showing her Yandere nature.
• Red Oni, Blue Oni: The aggressive, passionate and sociopathic Red Oni to Yukiteru's timid, cowardly and passive Blue Oni.
• Relationship Sabotage: One year prior to the series, she tried to sabotage Yuki's Love Confession to Moe. However, Moe rejected Yuki's confession even without Yuno's interference. It's notable that Yuno didn't try to directly harm Moe, as it was only when the Killing Game started that she became Yandere enough to attempt murder on potential love rivals.
• Religious and Mythological Theme Naming: Her name is confirmed to be a reference to the Roman goddess Juno (Hera in Greek).
• Romantic Fake–Real Turn: Despite her obsession with Yuki, she merely asked him to marry her because she was that desperate for a dream for the future. Yuno eventually admits this and tries to convince herself and Yuki that their love was an act both made up to use each other. However, Yuno realizes she did come to genuinely love Yuki, enough as to stab herself since she couldn't bring herself to kill him.
• Room Full of Crazy: An untouched room in Yuno's house that contains the corpses of her parents, and her second self who she murdered. Yuki finds it and ultimately changes the course of the game and the 2nd-world's timeline. Yuno eventually destroys the room and hides the evidence in a large pit behind her house.
• Rose-Haired Sweetie: Invoked. When she and Yuki are out of danger, she can act genuinely cheerful and romantic. As for the rest of the time, however, she's a Yandere Psycho Pink.
• Satellite Love Interest: Played remarkably straight with disturbing effect. Funnily enough, considering what she is, it ends up being Tropes Are Not Bad. Justified in that Yuno really has nothing in her life outside of Yuki. He's the only thing that keeps her relatively balanced most of the time.
• Savvy Guy, Energetic Girl: Yuki's strategic and rational Savvy Guy and Yuno's reckless and manic Energetic Girl.
• School Idol: She's described as a model student. She gets excellent grades, everybody likes her, and all the boys are crazy about her. Except the one she's stalking, of course.
• Self-Made Orphan: Yuno locked her adoptive parents in the same cage where her mother locked her and caused them to starve to death (although it wasn't her intention to kill them).
• Self-Proclaimed Love Interest: Ever since Yuki jokingly accepted her marriage proposal, Yuno actually believes they're engaged.
• Self-Serving Memory: She usually represses and alters her memories in ways she feels more comfortable with to prevent herself from going completely insane.
• Single-Target Sexuality: Extremely Yuki-sexual. She even will love any world's Yuki just because they are Yuki.
• Slasher Smile: Played with. The constant smile she sports on may as well be considered a Slasher Smile depending on context.
• Slippery Swimsuit: Loses her bikini top during the Water-Park Episode.
• Sour Supporter: She dislikes Tsubaki and keeps telling Yuki that they ought to just abandon her, but doesn't try to kill her and begrudgingly helps protect her when Yuki refuses to leave her. When Tsubaki turns on them, however, all bets are off.
• Stalker with a Crush: Yuno spends most of her time following Yuki around. She also likes to break into his house and send him hundreds of emails over the course of an hour.
• Stalking is Love: Double Subverted. At first, Yuki is seriously freaked out by Yuno's stalking and would like to get away from her, but he must let her stay close because she's his only true ally. Eventually, as he keeps relying on Yuno's protection, Yuki begins to accept Yuno's obsessive love to the point that he even states that he fell in love with Yuno because "she was always by his side."
• Star-Crossed Lovers: Yuno and Yuki have no future together, since one of them needs to die to complete the Survival Game, and leaving the game unfinished too long will cause the end of the world and they'll both die. At the end, 1st-world Yuno dies to ensure 2nd-world Yuki lives, but her memories are given to her 3rd-world self and she becomes god to be with Yuki.
• The Starscream: Played with. When she and Yuki are the only ones left in the Survival Game, she becomes his final enemy and hunts him down, trying to kill him in order to become god and go back in time. However, she only does it after he refuses to kill her (which would eventually result in both of them dying anyway), and when they realize the depth of their feelings for each other, the situation reverses. Yuki had wanted her to kill him once he convinced her not to repeat past mistakes, but she surprises him by killing herself to ensure Yuki lives on.
• Stepford Smiler: Extremely Unstable. She's usually brightly smiling, but it only serves to mask the insanity that lies beneath it.
• Straw Nihilist: To Yuno, everyone save for Yuki are dead weight and the world has no meaning without Yuki in it.
• Strong Girl, Smart Guy: Yuno is the heavy hitter while Yukiteru is The Strategist.
• Taking You with Me: Tries this when fighting Kurusu with the grenade Minene gave to Yuki, but it fails because the grenade turns out to be a flash grenade.
• Terms of Endangerment: In the dub, she likes giving pet names to Yuki. Given her stalker nature, it comes off just as creepy as it is cute.
• Trauma Conga Line: Her backstory in the 1st world. After years of horrific abuse at the hands of her mother, coupled with complete neglect from her father, she drugs and locks both of them in the cage her mother would use to punish her. She had hoped this would make them empathize with her and treat her better, but they end up starving to death, leaving her with no-one. She then becomes fixated on Yuki, survives the game with him, and after backing out of their Suicide Pact, discovers that she can't bring him back to life, thus losing the only important person left in her life. It's at this point that she snaps and her obsession with Yuki becomes violent and all-consuming.
• Tsundere: Surprisingly, Yuno plays this trope with her unique style after she decides to kill 2nd-world Yuki and tries to deny their love was real in the first place.
  Yuno: No, no no no! I've already abandoned this Yuki! I don't like him or anything. Not only that, I'm the one trying to kill him right now!
  Yuno's phone screen: Yuki said that he'd even die for me. I'm so happy!
• Uncanny Valley Girl: She's seen as a School Idol in her school, but she is actually an Ax-Crazy Yandere who keeps her family's skeletal remains in a room in her house.
• Undying Loyalty: She'll basically be devoted to her beloved Yuki her entire life.
• The Unfettered: She will do anything for Yuki and that includes killing all the other Diary Holders aiming for his life or just anyone who gets too close to him.
• Ungrateful Bitch: She kills Akise in spite of him sparing her life when he had the upper hand.
• Unholy Matrimony: After his corruption, she and Yuki become a couple of homicidal nutjobs.
• Unskilled, but Strong: Polar opposite of Yuki, in that her diary is almost completely useless except when paired with Yuki's, she's actually one of the strongest fighters. The only ones shown to best her in combat being Seventh's and Akise.
• Used to Be a Sweet Kid: Yuno wasn't always such a psycho. When Yuki and Minene go three years to the past it turns out that despite her abuse, she still was a hopeful and idealistic girl who still believed she could be happy with her parents. It was the events of the Diary Game in the first world that shattered her sanity.
• Villain Protagonist: She's the female lead, but she's also completely willing to kill anyone and through the series, she does very cruel and nasty things to a lot of people. Subverted in the later chapters when she becomes Yuki's enemy. She doubles back on that after she kills herself instead of him, though.
• Villainous Breakdown: Has one towards the end of the manga when Yuki refuses to kill her, prompting her to try to kill him, leap back in time again to restart the game and kill herself again. She fails, realizing she cannot kill Yuki and seals him in a Lotus-Eater Machine to escape him.
  Yuno Gasai: No…! No, no, no! I've already abandoned this Yuki! I don't like him or anything! Not only that… I'm the one trying to kill him right now!
• Villainous BSoD: It comes when she gets to see her 3rd-world self getting the love from her parents that she never got, and when Yuki escapes from the illusory world through The Power of Love.
• Villain with Good Publicity: A milder example: despite her psychopathic tendencies, Yuno is very good at maintaining a facade of normalcy in public. At the start of the series she is seen by everyone in school as an admirable, popular girl with nothing particularly off about her, aside from the fact that she likes to keep to herself. When Yuno reveals her true nature to Yuki, he is shocked, not just because of how crazy she is, but also because he would never have expected such a seemingly normal girl to be so insane.
• Violently Protective Girlfriend: She's willing to kill anyone who does as much as to get within 10 feet of Yuki.
• Wide Eyes and Shrunken Irises: Made much more apparent in the anime during her crazier moments.
• Woobie, Destroyer of Worlds: Yuno wants to keep the universe in an eternal time loop, forever replaying the Diary game, as this is the only way she believes she can stay with Yuki. She wants this so desperately because Yuki is probably one of the only kind people in her life, and her sole reason for living. Even if that means destroying entire universes/timelines to do it.
• Would Hurt a Child: Unlike Yuki, she has no problem offing Reisuke. She even chased him around Yuki's house with a hammer.
• Yandere: Though preceded by Yukako Yamagishi in Japanese media and Annie Wilkes in pop culture, Yuno has come to be acknowledged as the Trope Codifier of the archetype. What made Yuno famous (or infamous, for that matter) is her absolute ruthlessness in protecting her love interest, being ready to murder anyone who might take her Yuki from her. Bonus points for being named after Juno, one of the most yandere goddesses in ancient mythology. To Yuno's credit though, the show does give her reasons for having ended up so screwed in the head, and she eventually acknowledges her feelings for Yuki were based on dependency instead of love, at least until their feelings started to become genuine.
• Yank the Dog's Chain: Every time her relationship with Yuki looks like it's going somewhere, fate always barges in. In the end, they finally defeat it.

Tropes specific to her alternate selves

2nd World

• Couldn't Find a Pen: When the first Yuno performs a time leap to the 2nd-world and kills her second self, the latter writes "Help!" on the wall using her own blood.
• Last-Name Basis: Unlike the other Yunos, she refers to Yukiteru as "Amano-kun".
• Posthumous Character: She was killed by her own future self some time before the Survival Game started.
• Walking Spoiler: It's impossible to say anything about the 2nd World Yuno as a separate individual without spoiling the mere existence of multiple worlds.

3rd World

• Action Girl: She appears to have inherited the 1st-world Yuno's skill in combat, if her brief (and seemingly one-sided) fight against Akise in the Redial OVA is any indication.
• Doppelgänger Replacement Love Interest: 1st-world Yuno dies, but Yukiteru at the end gets together with her 3rd World counterpart, who was given her memories. As a bonus, since her counterpart had a happier life due to Yuki's intervention in that timeline, she isn't a Yandere.
• Earn Your Happy Ending: Redial is about the third Yuno's battle to gain her first self's memories and get her ultimate happy ending with Yuki.
• God Couple: She becomes god to be with Yuki, who had already become the god of the 2nd World.
• Happily Adopted: In the 3rd-world, Yuno's adoptive parents become good to her after her 1st-world self's attempt to murder her fails. Thanks to this, 3rd-world's Yuno doesn't grow up to have any of the mental problems she had in the previous timelines.
• Love Before First Sight: She never actually met Yukiteru before bringing him to the 3rd World, but she has inherited her 1st-world self's memories and love for him.
• Love Transcends Spacetime: She literally breaks the dimensional space between the timelines to meet Yukiteru and bring him to the 3rd World with her.
• Walking Spoiler: As with the 2nd World, acknowledging the 3rd World reveals the big twist of the series.