Beware The Nice Ones / Fan Works

Times where readers are reminded to Beware the Nice Ones in Fan Works.

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• A New Life Era has two characters who have demonstrated this trope: The Hacker, and his son, Moe, both beating up a bully more massive than they were at the age of 10.

Crossovers

• The Lamb in A Lamb In Hell is a friendly, cuddly little guy who likes getting pet and loves helping out Charlie, the Happy Hotel, and the followers of his cult. This cute, innocent nature is played up to the point where its easy to forget that he came to Hell because he thought crusading through it and killing any demons who stood in his way would make for a nice vacation. The first encounter with Sinners that doesn't end with The Lamb being immediately brushed off is an ambush from three minotaur-like demons, who The Lamb promptly defeats in a Curb-Stomp Battle before submitting them to Cold-Blooded Torture when they hypocritically beg for their lives, and the second was forgiving the demon who tricked him into the trap, paying his debts and asking him to be his guide in Hell.
• Shinji in Alpha and Omega is still the nice, unassuming guy he was in canon, even after becoming engaged to Aria T'loak. He also uses cryo rounds in shootouts because it doesn't smell as bad as incendiary rounds and makes for a less messy cleanup if you get to the bodies before the ice melts. Aria is slightly unnerved by his reasoning.
• In Avengers of the Ring, as in canon, Steve Rogers, Galadriel, and Wanda Maximoff can genuinely go to town on their enemies when they have to fight.
• A recurring motif in the Babylon 5/Robotech crossover The Battle for Narn:
  • Centauri emperor Kran is seen by some Centauri lords as too soft due to his social integration policies and unwillingness to militarily confront the Robotechnology-equipped Earth Alliance, and the Hyach (whose leaders hold a grudge against the Centauri for a renegade Centauri faction using mass drivers on their homeworld during a civil war) are waiting for the right moment to attack and finish off the Centauri Republic while preventing the signing of a non-aggression treaty that would give the League mining rights on the very rich world of Quadrant 7. Then lord Kodiro manages to pass a law that on the long run could potentially lead to a new Centauri civil war, and by the time the emperor is finished showing exactly why he's the one on the top in an entire race of Magnificent Bastards House Kodiro has ceased to exist (and was attacked even by the Minbari. Who knew they were being manipulated but went with it anyway because the information that caused them to attack was true), House Vintari (that caused the mess with Earth Alliance in the first place over their treatment of the Narn civilians) has suffered a defeat so crushing and humiliating that Curb-Stomp Battle doesn't even begin to describe it, lost its lord and forced to sell the planet, a Hyach armada of over two thousand ships has been annihilated in Centauri space, and the non-aggression treaty that has been signed doesn't include League mining rights and has the League forced to pay for the Centauri moving their ships to ambush the Hyach and to not support them against Centauri retaliation if they tried another stunt like that.
    Thanks the Maker that emperor Kran the Great was so soft... If he hadn't been, the galaxy would have burned.
  • Lord Vintari's son Turhan is another. He's a dutiful son, wouldn't want the Narn people treated as they are... And when his uncle (who's the main reason for the horrible treatment of the Narn) tries to continue fighting a losing battle against the EarthForce invasion of Narn he has him locked in a room with Narn women and declares it an accident. He's still a child.
  • As remarked more than once, the Centauri are what happens when a race of Actual Pacifists snaps and isn't given time to recover;
  • The Abbai as a whole are Actual Pacifists. They were in with Kran's plan to destroy the Hyach armada and get the non-aggression treaty signed;
  • The Hyach themselves are usually very peaceful. Thing is, their current leaders were traumatized children when the renegade Centauri attacked, and they secretly committed genocide on the other race of their homeworld (as the Centauri won't stop pointing out);
  • Earth Alliance as a whole is a peaceful power. Thing is, the entire population is armed for a reason, they have the most advanced technology bar the First Ones, and they aren't shy about using their superior firepower. Best shown in the orbital part of the battle for Narn, where EarthForce ships casually disabled Centauri ships as long as they didn't actually pose a danger to them (such as a squadron of antimatter-powered ships that came out of hyperspace too close to the battle fortress and was disintegrated by synchro cannon fire so that their antimatter fuel, that actually presented a danger if they rammed or exploded, would be dispersed and made harmless).
• Team RWBY in Boldores And Boomsticks are some of the nicest people ever to visit Earth. Casey had some trouble reconciling this with the brutally efficient way they were annihilating Grimm during the Battle of Aether Paradise.
• Child of the Storm:
  • Harry Potter: This version is a genuinely sweet kid. Even after his sweet nature is darkened by a Trauma Conga Line or two, he's still fundamentally decent and kind, and improving with therapy. On the other hand, he is also an Omega Class psychic, a fire-magic prodigy, and in the sequel, a budding Master Swordsman with a Super-Soldier plus physiology. That would make him formidable. What makes him dangerous is how he applies them when pushed too far. As more than one unwise enemy has found out, there are reasons that some fear he could be the Magneto... and in the sequel, why many fear he could be the next Doctor Strange.
  • Like father, like son: Thor is a Bruiser with a Soft Center who loves cuddling up to Jane and his son, a bit of a Pop-Cultured Badass, and takes the time to send down a light snow on Christmas, just because he's nice that way. He's also a Physical God with very few peers in raw power, roughly 1,500 years of combat experience, and an unbreakable hammer. A hammer that, as it turns out, he doesn't need to beat the Juggernaut to a whimpering pulp, which he does with his bare hands.
  • Steve Rogers: Adorkable Nice Guy who literally rescues kittens from trees and is absolutely useless with women. Also a One-Man Army and commander of the most Badass Crew in the world, if not the entire Nine Realms, who responds to Harry and Carol (the latter being his great-granddaughter) being kidnapped by the Red Room by calmly considering the situation, putting together a plan, then literally kicking down the doors of the Kremlin.
  • Charles Xavier is famous among those in the know for being a Cool Teacher and expert therapist who genuinely wants to help people. He's also famous for being the foremost telepath in the Nine Realms, and there is a reason no one wants to mess with him - the dismantling of Weapon X and the Breaking Speech he delivered to Essex, including the threat to 'peel his mind like an orange' being cases in point. The latter is especially notable, as Essex usually regards the prospect of torture or death with indifference, only being afraid of Doctor Strange. Xavier terrifies him into compliance without even raising his voice.
  • His old frenemy, Magneto, is also a kind and grandfatherly gentleman who's mellowed out somewhat with age. But he's also, well, Magneto, and everyone in the know treads cautiously at the mention of his name, with one senior member of the White Council name-checking him as "the greatest terror the world has seen since the Frost Giant Wars." Something he proves upon his entrance by effortlessly turning HYDRA's colossal vibranium-armoured and Destroyer-armed helicarrier to scrap. This is best summed up in the sequel when the Red Room made the spectacularly awful decision to kidnap his younger daughter, Lorna Dane, and Harry, his daughter's godson and treat them... poorly.
    "Good evening. My name is Magneto. You kidnapped my daughter. You kidnapped my daughter's godson. You tortured them both. You have twisted the latter into your weapon. I would like to discuss this. And once we are done, if you are very lucky... I might actually allow some of you to live."
  • Clark Kent, as per canon. He's an absolute sweetie. A genuinely Nice Guy. Humble, polite, a loving son, and a good friend. But when his buttons are pushed, he is a vicious in-fighter, enough to impress Harry. As Doctor Reynolds discovers, a Groin Attack delivered with Super-Strength is really not fun.
  • And then, of course, there's Bruce Banner. You wouldn't like him when he's angry.
• Izuku in Cinnamon and Spaghetti is just as much a Nice Guy as he is in canon, if not more so due to cheerfully befriending the government agents sent to spy on him. However, when push comes to shove, he's not afraid to unleash his Lovecraftian Superpower and slaughter his enemies. It says a lot that Eraserhead, one of the most unflappable heroes ever, is deathly afraid of him.
• In Code Geass: Paladins of Voltron, Shirley Fenette, for all that she is the Orange Paladin of Voltron, is a Nice Girl who despises the thought of hurting anyone. When Mao, after holding Nunnally hostage and forcing Lelouch to play an unwinnable game of chess, revealed Suzaku's dark secret and was about to kill Lelouch and blow up the Castle of Lions, Shirley planted an arrow through his chest in desperation. When Mao came back as a Robeast, Shirley deliberately repeated the previous method inside Voltron.
• Dante isn't exactly nice in Dante's Night at Freddy's, but he makes an attempt to make peace with all of the animatronics before he rips them limb from limb.
• Granted, Eija Satomi from Divine Blood isn't averse to dealing lethal force when necessary, but she is still extremely friendly, patient, kind and generally feels remorse when she is forced to kill. However, after the ghost of her second, divine mother killed the first blood-related adult other than her own mother, apparently out of no reason than spite, Eija's response was violent enough to catch the attention of an ongoing psychic battle between the soul(s) of a Humanoid Abomination and several Gods and Demons. The Humanoid Abomination ran away while almost everybody else watched Eija seal the ghost by drowning it in psychic representations of blood.
  • Later, Kasumi kills a banquet hall full of rebel gods using what appears to be blood magic-based poison, given that it was triggered by stabbing her own hand, which caused them to suddenly keel over one by one.
• Isabela's power to summon plants might seem harmless enough, but when confronting the Berkians who attacked Hiccup in The Dragon and the Butterfly, Snotlout in particular gets assaulted by vines and cacti more than once.
• Dungeon Keeper Ami is a kind, sweet Magical Girl, a warrior of love and justice who really prefers the "love" part. But she's been dumped in a world full of horrors beyond anything she ever saw from the Dark Kingdom, and she has had to adapt. For example, after trawling through the mind of Keeper Malleus, she's so completely disgusted by what she saw that she summarily snaps his neck with her Keeper powers.
• In Echoes of Yesterday, Taylor thinks Kara is the nicest person whom she has met, with "no a mean bone in her body". Nonetheless, Kara's also hot-tempered, impulsive, super-strong, and can't stand bullies, as a Nazi super-villain learned when she threw a truck at him.
• A recurring theme in Enter the Dragon is that Harry Potter is an incredibly friendly and cheerful young boy who's also a massive and incredibly powerful dragon. And even if he's not willing to retaliate, he's also responsible for 9.7% of the Goblin's monthly profits and they've gone to war over someone threatening a tenth of a percent of their profits before.
• Equestria Girls: A Fairly Odd Friendship: The Rainbooms, the Fairies, and Timmy show this at one point or another.
  • Sunset may be a better person, but she is still capable of being ruthless: When Timmy disobeys her and sneaks off to a skate park, she's so pissed off that she makes Timmy nearly wish for Vicky to come back. She later knocks Crocker off a balcony after seeing him humiliate and torture Timmy to get his magic.
  • Cosmo and Wanda are loving fairy godparents but will not hesitate to blow away something that threatens Timmy. Wanda has little problem with Timmy turning Sunset into a worm when the fairy thinks Sunset is an evil villain trying to take over the world. While she initially forgives the Dazzlings for using Timmy for wishes, she still forces them to do chores as punishment.
• Equestria Girls: Friendship Souls: Ditzy Doo has to be one of the nicest of Discord's allies. She's also a badass Action Mom, has no problem killing, and when she coldly threatens the girls to not get her daughter involved in any of this, it's clear it's a promise she'll keep.
  • Posey... DEAR GOD POSEY. Goes out of her way to hold back? Check. Borderline Shrinking Violet? Check. Apologetic Attacker? Check. Turns into an Ax-Crazy The Berserker when she stops holding back? Check. Her Zanpakuto is even called Kyoki (Bloodthirst). It's later stated that her change in personality is caused by Kyoki's influence.
  • The Lament is a good father, the Token Good Teammate of the Espada, and his friendliness even seems genuine. He's also the most Ax-Crazy out of all of them, and just as willing to kill as the other nine.
• Princess Henrietta in The Floating Castle shows the people of Aincrad why she's in charge after learning Albion has fallen to Reconquista and her beloved Wales is dead, by grinding a Floor Boss to death with a tornado made of water. In her words upon hearing of a monster even stronger than the one Kayaba died fighting against, "How wonderfully convenient. [She] had really been looking forward to a bit of violence today."
• In Frozen Turtles in Space, when Elsa is pushed to her limits by the ruthless Lord Dregg, she freezes his entire planet in eternal winter.
• In Harry Potter and the Ice Princess, Elsa is kind to everyone from house-elves to the eccentric Luna, but single-handedly destroys Aragog and his family to stop them being a threat in the future, and the only reason she didn't kill Tom Riddle in the Chamber of Secrets was because he didn't have a body she could hurt.
• In Harry and the Shipgirls, Hoppou is very much a Cheerful Child. However, if someone ever threatens her brother Harry or the Fleet of Laughter, she will not hesitate to remind you that she is still an Elder Abyssal Princess, with all of the power involved in that title.
  • Harry himself is no slouch. He is one of the nicest people in the whole setting...while also being a Military Brat. And as the reanimated pelt of Tamamo-no-Mae learned, pushing him past the Rage Breaking Point tends to end very badly for his enemies.
  • Cathy, the Sword of Saint Catherine, is the local Jeanne d'Archétype. She never raises her voice and is nothing but polite in everything she does. There are few people she will not offer forgiveness to. She also racked up a Dementor kill count firmly in the triple digits in a single battle after the Dementors attacked Harry.
• In Honey and Magic, while Matilda is sorted into Hufflepuff, and so kind that she even acted to defend Draco Malfoy when he was turned into a ferret by "Moody", during the Battle of Hogwarts she not only manages to save Tonks' life by confronting Bellatrix Lestrange despite only being a fourth-year but becomes so enraged that she uses wandless magic to kill three Death Eaters with a mass of improvised weapons (ranging from rubble to crystal balls) after said Death Eaters kill one of her friends.
• In Ice Fury, Wintergale- the last Ice Fury- is typically smart, playful, and serene, but push her too far and she will turn nasty, as most keenly demonstrated when dragon trapper Sigurd attempts to kill Elsa; Wintergale proceeds to strike his limbs with ice and then throw him around like a rag doll before breaking his neck.
• If Wishes Were Ponies: Twilight is one of the nicest ponies in Equestria and is a loving, protective adopted mother for Harry. But she's also one of the most powerful ponies in Equestria, and anyone who threatens the life/well-being of her son will face consequences. Dumbledore learns this the hard way when Harry calls Twilight for help when he runs into danger during his detention in the Forbidden Forest, and she not only brings one hundred of Equestria's finest but she tears into Dumbledore for thinking such a detention was a good idea in the first place.
• Schneizel is considered something of a joke in The Illusive Empire, folding to even the slightest bit of pressure from Britannia's many enemies. Yet, for reasons Guinevere doesn't understand, every one of those enemies is also desperate to see him removed from power. Guinevere refuses to even consider trying to overthrow Schneizel since they both know he was the one to have Odysseus and his mother assassinated and Schneizel's made it quite clear that he'll do the same to her if she ever moves against him.
• The Infinite Loops:
  • The inhabitants of Equestria have declared their universe a sanctuary for all those caught up in the loops. That means they will not tolerate anything severely dangerous or morally wrong, and they have banished visitors to the moon for breaking the rules. This also extends when they find themselves in other, less caring universes.
    Twilight Sparkle: We love and tolerate others! And if this world insists on being this cruel, then we are going to love and tolerate with extreme prejudice! I have put right worlds much darker than this one, and I am NOT going to let this world defeat me! For the sake of harmony, for the sake of the people of Europa, we are going to END THIS SENSELESS WAR!
  • Fluttershy is even nicer than in canon due to long experience redeeming people, but also far more dangerous. Not only has she gotten over her canon self-doubt and crippling anxieties, but she's a master shapeshifter who prefers to spend her time as a wolf, is an extremely powerful druid, she knows how to use The Stare to full effect, and her adopted son is a Primarch, the Super Prototype version of a Super-Soldier. Batman himself notes in his contingency for Fluttershy that due to her close connection to Warhammer 40,000, she has more experience with lethal combat than any other Equestrian looper except possibly Twilight. Twilight felt guilty about killing a villain when she had no other choice and the woman ended up Back from the Dead anyway. Fluttershy has not voiced any guilt over the oceans of blood she has had to wade through when helping her son in the baseline 40K loop. She did minimize the killing, but "minimal killing" in 40K still means a lot of blood.
  • Interestingly, this trait has been used by other monsters. Naoki Kashima's Shadow was crafty and cruel enough to drive him insane at the worst possible moment, turning the Equestrians and everyone else they're friends with (a very large portion of the Multiverse) against him in order to paint him as a relentless monster when in reality he'd been hanging to his sanity by a thread he was tricked into snapping.
  • In a non pony example, we have Princess Peach. She is as sweet as can be to almost everyone she comes across. However, what most people forget is that she can fight back if she needs to. Her looper powers build on this. As such, it's not a very smart idea to make her mad as Grodus would learn the hard way.
  • Most loopers are like this. They are, for the most part, heroes who are eons old and are mostly just out to screw around at this point. But make any one of them mad and they will bring the full force of said eons worth of power down on you.
• Chloe Cerise in Infinity Train: Blossoming Trail is learning to come out of her shyness once she boards the Infinity Train. But when Lexi roars into her face about wanting (justified) revenge against Grace and Simon, she immediately whips out her donut holer as a threat to not mess with her. The chapter after that, she puts it to good use against the Erlking and his hunters in The Midnight Car.
  • In Chapter 11, we see through a Flashback that after Alpha Bitch Sara dumped paint all over her, hurt her brother, and then mocked how Chloe's father doesn't love her, this makes her snap and beat up her bully with the very same paint bucket, looking like she's covered in blood and then tell her classmates that if they ever do a prank like that again, she will kill them all kinds of dead.
• Inky Future has X. There's a good reason why Dr. Light put him through thirty years of ethical testing. And X is a genuinely nice dude who wants nothing more than for everyone to just get along, even in an alien future where humans have gone extinct, but push him too far, and that "infinite potential" comes out. Tartar finds this out the hard way after he blends Artemis, Orion, Iris, Axl, Ayane, and Ethan and then gloated about it to X to cause him the most emotional agony possible. X overclocks his systems and proceeds to take apart the Mega Man Killers and Genesis Unit singlehandedly all at the same time, and then basically tortures Tartar in retaliation, with the only thing stopping him from killing Tartar outright is the overclocking causing his body to give out.
• In Interventions, this is demonstrated by Peter Petrelli, Matt Parkman, and Willow Rosenberg in particular, as Peter helps Jessica take sadistic preacher Caleb apart to stop him being a future threat while Matt and Willow work together to make sure that Maury Parkman will never terrorise Molly Walker ever again.
• It's Always The Quiet Ones: Luna is a very sweet-natured person, but she can be pushed too far, and sees no problem with inviting Cthulhu to stop by Hogwarts during dinner.
• Xander in Jedi Harris is even more of a Nice Guy than in canon, having received and retained Obi-Wan's memories during Halloween. The other side of that is, well, he has Obi-Wan's memories. And powers. Which means that, with a year or two of training and practice, he is The Dreaded for the supernatural community in Sunnydale, as much as, if not more so than the Slayer herself. However, there are a lot of baddies who haven't heard of him...because you need to be alive (or at least undead) to spread stories, and that's more than you can say for most of the vampires and other nasties he's crossed.
• Ben Tennyson in JoJo's Alien Adventure is the kindest amongst the heroes, being the most averse to killing opponents and also having a severe case of Chronic Hero Syndrome. However, NEVER assume that he can't be vicious to his enemies if they harm innocent bystanders or his friends, and the imposter Captain Tennile, Forever, Devo, and Rubber Soul can all attest to this. When Rubber Soul engages in his infamous Kick the Dog moment, Ben is so enraged that even The Stoic Jotaro is left unsettled, and he ignores the Stand user's cowardly pleas for mercy at the end of the chapter.
• Kyon in Kyon: Big Damn Hero doesn't go looking for trouble. He really doesn't. But then someone goes after his True Companions, and he alternately beats them to a bloody pulp or dangles them out a window. And now he has the ability to wipe out most of a town in one shot.
• Last Child of Krypton: Shinji Ikari is as polite as his canon counterpart and as friendly as the hero he becomes in the story. But what is his response when Leliel attempts an early version of Asuka's infamous Mind Rape?
  Shinji: BURN
• In Lex Marks the Spot, Lex Luthor/Xander Harris convinces a group of bank robbers that the reason Flash doesn't have any truly repugnant villains in his city is that any time who crosses the Moral Event Horizon, Flash goes back in time and prevents them from being born, which also wipes out the Flash who went back in time and prevents a paradox. After the robbers drop their weapons and armor to flee in terror, Lex admits to the hostages that he made the whole thing up.
• In Like A Wish, Nunnally gains Geass after being sent back in time. She uses it in Saitama to make Cornelia (and her command staff but they were incidental) see Lelouch run through with a sword, demanding to know why Cornelia let Britannia kill him. The sight sends the entire command staff screaming from the command center and continues to haunt Cornelia afterwards.
• In The Man with No Name, the villain utterly fails to do this in regards to the Doctor.
  The Doctor: Do that and you will end your days screaming in the deep places of my mind.
  Big Bad: Y-you wouldn't do that! You can't!
  The Doctor: Why not? You would.
  Big Bad: B-but you're the Doctor!
  The Doctor: Ah, yes, that argument. Heard that one before. And you know me so well, do you? You called me a monster not long ago. But now–ah, now you plead for the Doctor, the compassionate, merciful, pacifist Doctor.
• Gray Ghost in Manehattan's Lone Guardian is very laid-back and friendly, albeit rather detached from reality in the mistaking-her-reflection-for-another-pony sense of the word. It goes against her nature to hold a grudge, and she's quick to forgive and forget. However, she's extremely protective of her family. Threatening or antagonizing them, or even just taking her children out of her sight without her permission, means that it won't matter if you're a horror storyteller like Drama Heart or a battle-hardened soldier like Leviathan: she will make you feel fear.
• The Many Dates of Danny Fenton: Danny IS a nice, easy-going guy who treats the girls he dates with respect and consideration... but he also is not someone you want mad at you.
• Maria Campbell of the Astral Clocktower:
  • Maria's mental state is occasionally represented by a few different personas: The Noble, the Huntress, the Light Mage, and the Child. The Child, being the little girl who Maria could never allow herself to be, mostly just wants to cuddle with her mother and sometimes be told she's doing a good job. That is, until Maria's mother is kidnapped, and the Child is the one screaming for blood the most. The Huntress has to tell her to sit down and be quiet, because they have to find the enemy first.
  • Katarina really is just a genuinely nice person down to her very soul. However, she has also been doing sword training diligently since she was a child, and repeatedly surprises trained knights with her skill. When she finally gets a chance to use her sword (which she deliberately asked for not to have any sharp edges) in real combat, she's constantly apologizing to the people she's fighting... and she also leaves behind a very large pile of unconscious bodies.
• Mass Effect The Equestrian Equation:
  • This is a racial trait of Equestrians and their ancient ancestors, the Equines. They are, and were, friendly, cooperative, and believers in the Last-Second Chance. That said, they would and do deal swiftly and with overwhelming force against those who refuse to play nice.
  • It's further backed up by biological instinct; amongst Equestrians, conflict typically takes the form of getting up in each other's face, then a staring contest, and only then in violence if neither backs down. Other races don't get that level of generosity; if they don't back down when the Equestrian starts getting aggressive back, then the Equestrian will attack. Dr. Milligan finds this out the hard way and is crushed to death by Twilight Sparkle's biotic powers, then thrown into the heart of an artificial star, for attacking Shephard and trying to commit genocide on the Equestrians in hopes of claiming the technological lore of their ancestors.
  • The Codex describes how the first and only major war the Equines had with another race went down. To put it simply, they annihilated their enemy militarily, economically, and politically, leaving not a trace behind.
• Matsu in Matsu's Sekirei is something of both a Cool Big Sis and future lover for her Ashikabi Harry Potter. She also uses her hacking skills to completely destroy the Dursley family. And when Dumbledore and a few other professors arrive to "collect" Harry and bring him to Hogwarts, Matsu reads their minds to learn they plan on taking Harry no matter what and Dumbledore fully intends to have Harry die "for the Greater Good". Matsu spends the entire meeting plastering their faces on every International Most Wanted List she can and planning for their eventual attempted kidnapping/blackmail attempts. Even if that means unleashing the entire Sekirei species (including the violent psychopathic ones) upon the Wizarding World and declaring full-out war.
• In Neither a Bird nor a Plane, it's Deku!, Izuku is still a kind-hearted young man who doesn't want to hurt anyone. However, he's also Kryptonian, meaning that he's armed with a vast array of potentially lethal powers. He can crush bone with a love tap, slice through robots with his Heat Vision, and freeze nearly anything solid with his Super-Breath. Even when faced with Super-Strength Quirks, he can easily overpower most of them with a fraction of his full power. The fact that he nearly killed Katsuki when he was younger terrifies him into inaction at first, but he's a force to be reckoned with once he finally jumps into the fray.
• In New Look Series: Link's New Look, the usually sweet and girly Princess Peach gives the titular character a Death Glare once she finds out that he snuck into her room without permission, uses Obfuscating Stupidity to trick Link into dressing up in her clothes, and finally in part 2 decides to follow up on it by putting him in an And I Must Scream fate for the next three months.
• The Night Unfurls:
  • A non-action example, Celestine is The High Queen, benevolent and compassionate. The rebels in the Rebel Scum Arc clearly think that she would pay any price for appealing for peace. Being Black Dog supporters, they are more than willing to take advantage of that and set a price as high as possible. Her response is to give out the order, to meet them with fire and sword, to scour them from the capital without hesitation. Proving that she has come a long way, Celestine doubles down on the punitive measures imposed on the nobility, censuring those who have sponsored the rebellion and the Black Dogs.
  • Evetta is a sweet, gentle doll through and through, nary a violent bone in her body. Threaten her in any way, and she'll give them a friendly reminder that she chooses to be passive by sending an impassive glance to make them change their mind. If that doesn't work, then strangling or maiming them with her mind should do.
• In On the Run, after Letty has spent some time helping Clark deal with some personal matters after he saved her life, once she reunites with Dom she compares Clark to a mix of Brian and Vince; he's generally a kind man, but once someone angers him he's a very dangerous person to cross.
• A Peaceful Afterlife: Charlie is the classic all-loving, sweet as sugar princess....however, she's the princess of 'Hell' and the daughter of a fallen archangel and the first demon, and possessing all the power such breeding entails. When pushed to her limit, Charlie kills the exorcist's God-Given created with his powers and holds him in place to let Kira's final attack kill him.^note God Given cannot manage to get out of her grip despite Charlie being frozen in time.
• The Pirate's Soldier: Mihoshi Kuramitsu, just like in her canon series, is a complete sweetheart to everyone. When her brother Misao conspires to kidnap her fiancé Heero with Kagato, she's the one who conducts the interrogation, although not before she delivers a hard slap and verbally tears him down for what he did. Misao himself seems terrified at the sight.
• Shirou Emiya is favorably compared to Buddha in Promises of a Wandering Hero, with even the residents of the Hinata Inn admitting he's a kind, forgiving, and understanding man. He can also defeat even Motoko's older sister Tsuruko and if he's willing to kill, he can take on her entire clan and win.
• Yayoi Kise in Respect. What happens when a weak, timid crybaby gets the power to fight back against The Bully with a Puella Magi's power? Answer: An accidental murder, a Start of Darkness, Sanity Slippage, and eventually laying waste to a town.
• Scarlet Lady: Alongside Marinette, Rose is one of the sweetest people in her grade, as she loves children, unicorns, and kind-hearted people (which is what endears her to Prince Ali). That's what makes her such a powerful fighter as Pigella, as her reaction to learning that Hawkmoth took advantage of a little boy who was afraid of a scary movie is to say that she's going to make sure Hawkmoth never does this to him again.
• The Secret Return of Alex Mack: Alex is one of the nicest, kindest people you'll ever meet. She's also Terawatt, the world's most powerful superheroine, and will beat you unconscious — as nicely as possible — if you try anything.
  Klar: Now Lieutenant Lupo looks like she could rip your head off, and maybe she’d do it if you ticked her off. Okay, Hanna has that look in her eye sometimes. You know, that 'I can take you from way over here' look. But Alex looks like if you were mean to her, she'd run home and cry.^note Alex's most recent missions at this point included killing a 150-foot spider and its horde of car-sized babies, disabling a CIA hunter-killer team, and beating Azure Crush — who can throw cars and shrug off bullets — in close combat.
• The pacifistic Liir are more than happy to explain this trope to the Batarians in the Mass Effect/Sword of the Stars story Shepherd Of The Stars. After covertly infecting them with a lethal retro-plague, the Liir proceed to unload a Curb-Stomp Battle so brutal it almost drives the Batarians to total extinction. Even the other Sword of the Stars races are shocked.
• Nunnally Lamperouge in Six Paths of Rebellion is a sweet innocent girl hiding endless rage and hatred for what Britannia did to her and Lelouch, and C.C. has granted her the Rinnegan which also restored the memories the Emperor sealed away. When V.V. comes to kidnap her, Nunnally lets out seven years of pain and anger on him, swearing that only when he fully understands her pain will he have her permission to die.
• Sonic Generations: Friendship is Timeless: Do not make Amy angry. Spike found that out the hard way.
  Spike: WHY WOULD YOU LEAVE ME WITH SOMEONE LIKE HER?
  Sonic: WHY DO YOU THINK I SAID DON'T MAKE HER ANGRY? WHAT, YOU THINK I WAS BEING CUTE?
• A Triangle in the Stars: While he definitely wasn't nice in the start, Bill Cipher comes to genuinely care about Steven. So any and all attempts to hurt the boy will make him angry.
  • Steven Universe is a more played straight example, just like his canon counterpart.
  • Wendy Corduroy, usually laidback, kind and calm, doesn't hesitate to threaten Bill in Chapter Eleven. It falls flat, since he's still stronger, but they even engage in a "glaring contest" afterwards. It doesn't even stop until Steven comes back and drags Bill away.
  • There's also Sadie, who stands up to Bill and keeps him from messing up the school as badly as he initially wanted, Peridot, whose metal powers activate with feelings of frustration and Kryptos, who banged his hands on the bubble keeping him and the remaining Henchmaniacs trapped upon hearing that Pyronica betrayed Bill.
• When Summoning, Please Watch the Wording: has both Crowley (the Fallen Angel who didn't so much fall as 'saunter vaguely downwards') and his old friend (professionally, a Friendly Enemy) and Aziraphale, after some wannabe Satanists cross Moral Event Horizon to summon the wrong yellow-eyed demon. Initially, Crowley was just annoyed. Then he saw how they'd done it. He promptly invokes this with a 'waxy' Slasher Smile, tricking them into summoning Aziraphale, who at first seems merely miffed... then Crowley shows them what they did. And they taunt him. Cue divine wrath and Cruel Mercy that, as Crowley notes, would have impressed some of his colleagues Down Below.
  Aziraphale's expression was like thunder. "Come to me, my child," he said, his tone as cutting as diamonds. "And I will show you a true wonder of a miracle!"
• The Wizard in the Shadows:
  • Harry, after he opens up a little. Nice, friendly, caring, and slightly but harmlessly mad. Until you hurt someone he cares about. Then you are reminded that he earned his status as The Dreaded for the forces of evil, and that he is the most powerful mortal wizard alive. When Harry gets angry, craters the size of soccer pitches are left behind and the Nazgul make for the hills.
  • Emrys. Cheerful Original Character, Tagalong Kid, and Servile Snarker. Then he gets dangerous when he finds out what happened to his sister. He grabs the rapist and shoves his head underwater, fully intent on drowning him. He's fifteen. And this is before he becomes an Empowered Badass Normal.
• The Weaver of Fate, aka Lúthien Tinúviel, is Zulu Squad no Tsukaima's closest thing to a Big Good, she is responsible for rescuing members of the Damned 33rd from Dubai and sending them to better worlds where they can do good. She is also the mentor/love interest to the story's protagonist, but god help you if you torture or threaten any of her charges, as two Reconquista thugs who attacked her found out the hard way.
• Lincoln in A Loud Among Demons stands out among the denizens of Hell with his genuinely kindhearted nature and preferring to see the good in other people, even in those as flawed as his co-workers. Despite this, however, Lincoln will not hesitate to call you out of your behavior if you push him enough. Piss him off real good, and his gradually developing demonic half activates.

Ah! My Goddess

• Jago from Ah! Archfall!. Nice guy. But at the bare minimum of his power, he flattened three bikers WHILE DRUNK. And if he uses Jupiter...

Aaahh!!! Real Monsters

• The trope is mentioned by name in An Ounce Of Prevention when an enraged Slickis is threatening Zimbo upon learning that the bee monster's taunts caused Ickis to develop bulimia.

Avatar: The Last Airbender

• Absolute Trust:
  • In Chapter 23, Katara, usually the one who calls Alec out for his foul mouth, curses without hesitation or apology when she learns that Toph's parents not only never gave her "The Talk," but never planned to, with the intention of excusing her monthly periods as her simply being sick, for the rest of her life. The fact that they're on the run from the Fire Nation is the only thing that keeps her from flying back to Gaoling to do more than just swear at them.
  • In Chapter 28, Azula makes the near-fatal mistake of insulting Kya while not focusing on Katara. She knocks Azula out with one brutal tidal wave and Aang has to hold her back from finishing the job.
• In Field of Innocence, The Wise Prince Lu Ten is sweet, polite, and compassionate. But spirits help you if you ever harm his little cousins and trigger his Big Brother Instinct.
  Lu Ten: Now you listen to me, Uncle, and listen good. If you hurt either one of those kids again, if you say anything to make them feel bad, if you so much as look at them wrong, I will face you in an Agni Kai and I will break and humiliate you in front of the whole court. I don't care who you are. I don't care if our family is watching. I'll hold nothing back, I will destroy you!

The Beatles

• Oh, you do not want to piss off the four in With Strings Attached or The Keys Stand Alone: The Soft World. They're decent guys (Deadpan Snarkers though they can be) and Actual Pacifists who just want to be left alone and who wouldn't dream of initiating attacks on anyone. But press them too far and they will do their damnedest to nonlethally destroy you.
  • In Strings, the four completely wreck both the Raleka's and the skahs's dreams by taking the Vasyn for themselves.
  • More deliberately in Keys, they wreck the armor and weapons of anyone who annoys them, they drop people out 10-story windows (though they catch them at the bottom), they strip them naked and imprint humiliating words on them, and they verbally destroy them.
    • Don't fuck with Nine Thousands!

Bleach

• Downfall is chock full of (relatively) nice, non-combative people. When they decide to get busy it tends to get ugly, mostly because the non-aggressive characters are usually the more powerful ones.
• Part of Orihime's Character Development in A Protector's Pride is her letting all her pent-up anger out. The first time it happens, she easily holds off Yammy and takes one of his arms out.
• Kyouraku's zanpakutou, Kyoukotsu warns Ichigo in Sight that Kyouraku Shunsui and Ukitake Juushirou are very dangerous despite their kind natures.

Calvin and Hobbes

• Hobbes in Calvin & Hobbes: The Series normally flees at any sign of danger and is generally kind of a drag. He also doesn't like Sherman, a snooty hamster, and the feeling is mutual. When Sherman pushes him too far in "Remember", he actually attempts to kill him, and likely would have if it weren't for Calvin's Time Pauser.

Chip 'n Dale: Rescue Rangers

• In Of Mice and Mayhem, Gadget, usually the epitome of kindness, attacks the men who were after her when Chip gets shot trying to protect her.

Chrono Cross

• In Fellowship, Guile is a kind and soft-spoken Black Mage who treats his little friends like his children and sometimes sheds Tender Tears. However, if you hurt or threaten any of his 'children', he will snap and proceed to pulverize you.

Danganronpa

• In Everyday Life with Ultimate Girls, Makoto Naegi is generally considered one of the gentlest people that one can know and is an absolute Nice Guy and All-Loving Hero. However, he does not take kindly to seeing those he cares about being threatened in any way, which also makes him a Chick Magnet, though he is somewhat oblivious to this.
  • During an attempted coup and assassination on Sonia Nevermind, he sees her treacherous ambassador Wudagest attempt to shoot her, pushing her out of the way and getting shot in the shoulder for his troubles. When Wudagest accuses her of being no different than her evil ancestors, Makoto breaks down that he does not trust the people while Sonia's faith is to her country and her people.
  • When he stumbles upon Aoi Asahina being insulted by her date (a male model) as sweaty and unfeminine when she calls him out for getting mad at a girl for dropping ice cream on his outfit (she was undergoing a crisis of femininity, and was tricked by Junko Enoshima into thinking that a date would help her self-esteem) out of jealousy due to others paying attention to her instead of him, Makoto punches him and gives him a brutal "The Reason You Suck" Speech, humiliating him.
  • After Hiyoko Saonoji pulls a number of pranks with the potential for severe harm (putting tacks in the shoes of Sayaka Maizono, nearly tricking Akane Owari into eating poison ivy which could have killed her, and kicking a ladder being used by her favorite target Mikan Tsumiki), Makoto decides he's had enough of her bratty behavior and tricks her into drinking mouthwash disguised as fruit punch.
    • That being said, when her insulting two drunk delinquents leads to her nearly getting raped, Makoto (who was getting agar-agar for anmitsu in an attempt to rebuild relations between her and the rest of the class) immediately springs into action and defends her, taking several punches but refusing to divulge her location. It's these actions that make her undergo a Heel Realization and fall for him.
• Makoto is a very kind-hearted and loving person in The Naekawa Project, but his anger is something that terrifies Toko. When Shizuku, one of her mothers, attempts to slap her after Toko spells out how abusive she was, he grabs her hand in a vice-like grip, simply telling her to shut up, replacing her anger with fear.

The DCU

• In But Doctor, I Am Pagliacci, Jack Napier (the Joker with his sanity restored) is a friendly, noble person, but make no mistake, he's still the Joker. And without his insanity handicapping him, he's able to repeatedly humiliate the Justice League (who've been corrupted) and put together a team-up fully capable of handing the Justice League their asses on a platter.
• DC Nation - Dr. Light had unleashed a toxin that was killing all prepubescent children in North America as revenge for his Mind Rape at the hands of the JLA, just to make sure that the heroes' children suffered. He captured Sue Dibny to "finish what he started." A JLA strike team was sent after him. Light had them all on the ropes and was dangerously close to killing the Elongated Man when Sue broke out of her holding cell, and armed with Hal Jordan's ring, proceeded to open up a literal can of whoop-ass on him while cussing him out in English and Yiddish.
  • Nationverse actually loves this Trope. Hypertime elemental (and Cloud Cuckoo Lander) Shift is normally pretty laid back. When Shift's zombie grandfather almost killed him (during Shift and Miss Martian's first date date), Miss Martian morphed into her giant, scary white martian form and tore the zombie to little pieces. When the zombie grandpa got better moments later, Shift snapped and stranded him in a dead alternate Hypertime after beating him up at superspeed. He thought to himself (in his normal fragmented manner), after the blur of his own movements, "Tastes terrible. Zombies taste like old Slim Jims. Makes sense. Need mouthwash after this." The nice one bit off a chunk of his undead grandfather.
  • Another example is Fauna's "freak out" stage. Fauna is a sweet-natured, Technical Pacifist Granola Girl with abilities (she'll never call them powers) close to Beast Boy's. Push her to the point where her shapeshifting snaps her brain, and she will come at you with everything, including cobra venom.
• Hellsister Trilogy Kara is her family's kindest and most empathetic member, as well as a Physical God with a fierce temper, which is because she explodes when Darkseid almost kills her cousin, alternate self and boyfriend. She doesn't win because Darkseid vs anybody battles can only end in one way, but she still gets several good licks before going down.
  Supergirl: I've been through hell and a half in this last week. I've fought Blackstarr, Eclipso, the Zoners, Kralik, the Golem, and I'm probably leaving some out. I almost got zombified because of you. Now you've hurt the man I love, and my cousin, and my friends. I didn't want to do this. I didn't want to do any of it. I hate fighting. But I promise you, Darkseid, if you don't restore them and surrender, you're never getting up from this floor in one piece. I swear it!
• Kara of Rokyn: Kara is kind and compassionate enough to go out of her way to help someone who bullied and harassed her at a personal level only because she realized that person was leading a miserable life. Hurt someone else, though, and she'll pummel you to the ground. Threaten a mother and her son and she'll not even feel sorry about it.
  Kara: So you feel like using super-strength on a normal woman and her child. I don't have the slightest regret about what I'm about to do.

Digimon

• Koushiro "Izzy" Izumi is one of the 3 nicest boys in the Digidestineds. In The Truth by Cybra, he discovers that his biological parents were murdered, is nearly drowned and finally nearly killed by his parents' murderer in a replica of their "accident". How does our sweet little computer genius react? By swiping the guy's gun and holding him at point-blank range until he gets the full story out of the guy. This not only scares the doctor he's threatening but also the watching Matt. The best part? The gun didn't have any bullets left and when Izzy is asked why he held the man at gunpoint if he knew he couldn't shoot him, he replies "I wanted him to know how it feels to be toyed with." Moral: Do not mess with Izzy or the people he cares about.
• Takato from the Tamers Forever Series. A sweet, friendly boy who will absolutely DESTROY you if you anger him. — and this is Not Hyperbole, he will annihilate you.

Discworld

• In There's Nothing Like a Fresh Pair of Eyes, student Assassin Catherine Perry-Bowen gets conclusively even with school bully Lucinda Rust after years of humiliation in the sword-fighting class. It helps that her vision and ability to fight have been enhanced somewhat...

Dragon Age

• The dwarven noble protagonist in Dragon Age: The Crown of Thorns expected Faren, the DC, to hate him when he revealed to him that he always knew Rica was Bhelen's concubine and had never said anything. Faren doesn't really end up hating him but, since he hates Bhelen's guts (among other, deeper reasons), he still delivers a No-Holds-Barred Beatdown to the prince, leaving him with a broken jaw and a couple of snapped ribs for good measure, plus a swollen eye. At least Faren ends up regretting it, after getting a What the Hell, Hero? speech from Kallian Tabirs, the city elf warden and his love interest, plus finding out just why the guy withheld that from him. He only really realizes just how badly he flipped out after remembering that the DN has a particular problem that prevents healing magic from working on him, so Wynne can't just snap her fingers and make the horrid pain go away.

Dragon Ball

• Dragon Ball Z: Dynasty has a rare and special kind of Saiyans called Alpha-Types, who are described as usually very kind and friendly, but once they lose their temper, they unleash a massive hidden power and their personality takes a 180º turn. The only recorded Alpha Type was Cassava, Vegeta's mother, whom his father married hoping to pass her power onto his descendency, and Bardock believes Gohan might be one as well. He also mentions that "some brat King Vegeta had banished" might be an Alpha Type too.

Emergency!

• Yes, Roy is about the second quietest, most even-tempered guy in the station after Mike. But in this series, you'll be very sorry if you try to hurt his family or Johnny. He *will* get physical and in your face if necessary to protect them.

Encanto

• When Isabela, Luisa, and Mirabel overhear a random villager that they are better off without their father Bruno in ⫚ - His Daughters, The Miracles of the family, Isabel has the man strung up with vines and forces him to apologize.

"Fairy Tail''

• The Gender Bend Cliche: Luca Heartfilia, the male version of Lucy, is a proper gentleman that is always kind and understanding to many of his guildmates. That said, like his canon self and other Fairy Tail mages, he's more than willing to fight to protect his love ones, such as delivering a Groin Attack to Jose when he was bragging about using the job to take Luca back to his father as an excuse for Phantom Lord to crush Fairy Tail or deliver a Curb-Stomp Battle to Evergreen when she petrified their guildmates during the Battle of Fairy Tail arc.

Fallout

• Fallout: Europa: Austin is a pretty amicable guy and fun to be around and talk to. He's also responsible for nearly a dozen on-screen deaths by chapter 5.
  • All over the place really. It seems that the best way to survive in Europe is to automatically assume, no matter their mannerisms and level of kindness, that they are packing heat and that they will end your sorry existence if you give them cause.

The Familiar of Zero

• The Pope Victor of Halkagenia in Zero's Bullet is a nice, soft-spoken boy who is the first pope in centuries to use his power to help the poor and downtrodden. He also has his own version of Iscariot working for him and orders all those who tried to overthrow him executed.

Final Fantasy VII

• Us and Them: Aeris is normally very sweet and friendly, but if you make her mad...watch out. One character even notes nervously how she seems so sweet and innocent most of the time.

Fire Emblem

• A Brighter Dark: When Sakura is captured by Nohrian bandits led by Hans, the first thing she tries to do when she ends up alone with him is shank him. After his Villainous Rescue, when he claims he can do whatever he wants to her because he is her only hope of surviving, she simply retorts that her good word is the only thing that will save him from the gallows once they reach Hoshido.

Firefly

• In Freedom To The Free, Wash, Kaylee, River, and Simon are abducted, enslaved, and endure a lot before they’re rescued. Back on the ship, Jayne makes a jerkass comment about Simon, who endured much more than the rest trying to protect them. Wash is about the least threatening guy around. He’s funny, lighthearted, and playful. But Jayne pushes him to his Rage Breaking Point and Wash grabs Zoe’s gun and turns it on Jayne.
  Wash: "That boy saved us. He protected us. You have no idea..." Wash's voice shook with anger. "If you ever say something like that again. I will kill you. No - if you even think it - I'll know, and I will drop your ass off in Reaver territory!"

Fullmetal Alchemist

• build your wings on the way down: When the homunculus Greed teases Nina (who has performed human transmutation in this story to bring her adopted father Maes Hughes back to life) just before she explains her plan to stop Father from turning Amestris into a Philosopher's Stone, she has a very quick comeback.
  "I'm one of five people who could kill you and make it stick. Be nice to me."
• There's been no true hints to it in the story itself, but Word of God is that out of the main four in The Seven Names of Envy Angevin (Envy, Ed, Ling, Russell), Russell is actually the most dangerous, despite his general laziness, apathy, and sarcasm.

Good Omens

• Uriel in Manchester Lost. One moment he is falling off the edge of heaven (which Raphael notes has no edges) and forgetting how to fly, as well as being a general Cloud Cuckoolander the next he is throwing the 3rd most powerful demon in hell through several buildings and the remains are sizzling and in bits. Then, after a long battle, he nearly succeeds in ripping Lucifer in half, and throws him all over the place.
  • Aziraphale in the same fic. After he briefly falls, he gets so angry, that even Beelzebub Lucifer's second is frightened of him. Unfortunately he is distracted. Later however, he sets himself on fire with holy flames, leading to him dispatching Beelzebub in a Taking You with Me moment.
  • In fact, this trope is such an essential part of this fic that one of the two rules of Hell is "LEAVE THE NICE ONES ALONE."

Harry Potter

• In Dumbledore's Army and the Year of Darkness, Dennis Creevey is one of the sweetest, nicest boys you could ask for... until the Death Eaters finally push him too far. "AVADA KEDAVRA YOU SON OF A BITCH!"
• Harry Potter and the Methods of Rationality has an army. They're named The Sunshine Regiment, their badge is a smiley face, they make no secret that they're fighting for Good in the most Sickeningly Sweet way possible... and when the battle commences, they win. Their opponents are a child prodigy and a boy trained from birth as a death instrument.
• Padma Patil's description of Su Li in Happily Ever After:
  Padma: Unfailingly polite, gentle, calm, until you push her a little too far, and then she unleashes the little dragon. When that happens, you better run, far and fast.
• Hermione Learns a Thing: After seeing some of the potential of Hermione's research into psionics, from telekinesis with no known upper weight limit to unlimited free electricity generation to computer equipment decades ahead of its time, Jerry and Farouk realise that the British government will be extraordinarily keen to have her working for them by whatever means necessary, but also that it would be a very bad idea to try to force her to do something she doesn't want to do.
  Farouk: She's a very calm child and I think very unlikely to do anything dangerous, at least on purpose. In fact she's more aware of safety than most of my own students are. But… push anyone far enough and they're going to push back. She has a lot more methods to push back than most people do. So do her parents. And I would really not like to see what would happen if she was forced to get inventive…
• In Technomad's Fiat Justitia, Luna Lovegood, of all people, reacts very badly when her Daddy is brought to trial after the war for attempting to betray Harry. She goes all but berserk, leaps into the courtroom to stand in front of her father, and scares Kingsley Shacklebolt.

Heroes

• The Dark Fic Unmade gives us this in an instance of intense Psychological Horror when Emo Nice Guy Peter Petrelli (who also just happens to be a Person of Mass Destruction) goes on a Roaring Rampage of Revenge through Primatech after being tortured to the breaking point stopping only to free his new BFF Sylar. They Leave No Survivors.

Hetalia: Axis Powers

• Gankona, Unnachgiebig, Unità: Enduring a day of tension between Germany and Japan, Italy reached his Rage Breaking Point after Germany pulled a Browning Hi Power on Japan while Japan pulled out his katana on Germany.
• Grey Skies Universe: Because of England's actions and what he did to America after the failure of the initial American Revolution, Canada rebels against the British Empire and proves to be a force to be reckoned with. He will be free or die trying. He also trains with Russia to learn how to use his cold weather to his advantage.

hololive

• Holo-Chronicles: Tokino Sora is the absolute epitome of a Nice Girl... and also the World's Strongest Woman without a single shadow of a doubt. Yoruno Sora is what happens when the innate emotional inhibition of her Purity Trait is incapable of containing a flood of negative emotions running through her, and is not only stronger than Sora's normal state, but is also fully willing to destroy everything and everyone around her in the time she has before going back to normal, just so whoever pissed her off is gone.

The Hunger Games

• In Some Semblance of Meaning, heroine Vale Whitaker is probably one of the most sweet-natured, timid tributes in the Games. She hates the idea of harming another human being. This same girl lividly stabs another girl in the chest after the latter attacks Vale's district partner Kit, and after one of the Gamemakers' mutts kills Kit, Vale goes into what could be described as a berserker rage the next time she sees the mutt, jumping on it and hacking at it until it's dead and she passes out. To say nothing of the distrustful snark she unleashes on Obsidian Citrine, even if he's being perfectly friendly to her.

The Incredibles

• Rise of the Galeforces gives us Sarah Squall, who at first glance looks and acts like a fun person to be around. But as various foes can attest to, she is in fact a Cute Bruiser who can toss friggin' dinosaurs around like ragdolls. And fly. Well, she IS Stratogale after all...
  • It's probably not a good idea to mess with the rest of her family, either. Sarah's dad can drown you with a cupful of water and sic sea creatures on you, while her mom is a Gravity Master who can suck you into a black hole in ten seconds flat. Her uncle is a true dunderhead, but he can still kick your ass with either lightning, wind, water, or ice, whatever comes to mind first. Oh, and Terrordactyl? Suffice it to say that his name pretty much speaks for itself.
  • The Western Animation section provides more details on the OTHER Super Family Team, but special mention goes to Violet in this case, who develops into a savvy Combat Pragmatist. Special note goes to her literal Roaring Rampage of Revenge in Episode 4, which ends when, after single-handedly wiping the floor with the last of the Big Bad's armada, she gets a yanked chain and a Torso with a View thanks to his final bullet... and her temper goes completely off the rails, causing her to order him slaughtered, horribly and on-screen, in front of the entire cast. Shy as she is, this is the kind of girl who won't take an insult lying down, and isn't at all afraid to kill if she has to.

Invader Zim

• Karma Circle: Judgement: Mr. Elliot, Gaz's perpetually smiley and cheerful teacher, is one of those who assault her in the nightmare given to her by Daan Yel. And since Daan Yel created that nightmare by tapping into the subconsciouses of all of Gaz's victims, that implies this is how Mr. Elliot actually feels deep down.

Kill la Kill

• Satsuki Matoi from Maim de Maim is one of the nicest, silliest, and sweetest people one can hope to meet, however, pushing her the wrong way isn't in one's best interests. Oh, and if not her fighting on the battlefield you need to worry about, it's being in bed with her, as openly disclosed that she may be THE' naughtiest among her peers; perhaps more so than Ira and the guy's a total masochist.

Kingdom Hearts

• In Fill the Moon, when Demyx happens to witness Xigbar being slightly wounded by Captain Barbossa, that minor injury towards his lover is enough to get him to snap, summoning a hurricane and capsizing the Black Pearl, along with drowning around one hundred Heartless and keeping the entire pirate crew at bay with the power of his magic. Don't piss off Demmy-kins.
  • Another nice, cute, sweet messiah you don't piss off? The little girl called Senayax. Once you lay a finger on her family or her pet Heartless, you are in for an absolute world of hurt. Hollowmoon, the Eldritch Abomination that lives inside her, and Kingdom Hearts itself? They found that fact out the hard way.
• In Second Chance, Sora has been bullied by his classmate Zenos for over a year because of his Not-So-Imaginary Friend Ventus. It comes to a head during a trip to the swimming pool when Sora accidentally outs Zenos' crush on Kairi and Zenos pushes him into the pool before mocking him for having a panic attack. Ven takes control of Sora's body to let him calm down, before turning to Zenos.
  Ven: You think Sora’s a baby? Who’s the one who just had a temper tantrum and pushed him in the pool? (walks up to him) You think you’re tough? That you’re not afraid of anything? Well, let me tell you, that’s a lie. Everyone has fear in their hearts about something. Sora? He nearly drowned two years ago when he got caught in a riptide. You think you would come out of that unaffected?
  Zenos: What kind of game are you playing Sora?
  Ven: Sora’s not here right now Zenos. You wanted to meet me so bad? Well, here I am. Name’s Ven. I’d say it’s a pleasure, but it’s not. All year you’ve been bullying my little brother. Picking on him and his friends and all for what? A crush? Newsflash, if you like someone the way to their heart isn’t through being mean to their friends! You could have been nice, and we would have welcomed you. (shakes his head in disgust at Zenos' pettiness) You’re a bully and a coward Zenos. And if you think I’m going to let this continue you’re wrong. This is the last time you hurt my little brother. And I’ll know if you do. Everything Sora sees? I see. If you so much as touch him, I’ll make sure you don’t get away with it. I’ll tell the teachers, my mothers, and if that doesn’t work? I’ll protect him from you myself. That’s a promise.

Life Is Strange

• All That is Left Behind has William Price, who's an absolute gentleman towards Joyce, a kind and supportive father figure to Chloe, and an overall Nice Guy in general. He's also not afraid to confront Damon Merrick when the latter tries to demand his money from Drew, and while he does convince Drew to pay Damon what he's owed, he follows up by laying Damon out with a single punch and warning him to never again threaten a minor within his hearing.

The Lion King

• In The Lion King Adventures, a few of the characters are very sweet. But get on their wrong side and you're in trouble.
  • Simba eventually becomes a vicious killer in Series Five after the death of his parents.
  • Nala becomes hell-bent on murdering Simba after the trio disbands in Changes.
  • Haiba murders Tama in cold blood when she implies that she's going to rape him.
  • Tojo becomes corrupted by the power of Hago's staff in Tojo's Tyranny, thus resulting in the consumption of his soul and eventual death.
  • Cameron as well, when he snaps and becomes a giant evil version of himself.

Lilo & Stitch

• Yes, Jumba has more-or-less retired from the "evil" part of being an Evil Genius, perfectly happy to live on Earth as Lilo's quirky "uncle" with hundreds of his reformed experiments being appreciated. In Aloha, he's still that same character. But as violent and dangerous as the various experiments were before they were turned from bad to good, which the Grand Councilwoman realized after Lilo was kidnapped, Jumba is the one that purposefully made them in the first place. And when a member of his 'ohana goes missing, he's perfectly able to go back to being a dangerous Evil Genius if it means helping save Lilo.

The Loud House

• Leni Loud is generally considered the nicest of her sisters but in Mall Rats, when she figures out that some jocks she and Lincoln run into at the mall are bullying her brother, she literally beats the stuffing out of them with skills she taught herself after taking the expression "fight or flight" literally.

Love Hina

• Implied in The Magic Goes Away. As Shinobu remembers all the abuse the other tenants have put Keitaro through, she finds herself contemplating her knife rack.
• Shinobu Maehara in The Merry Killers is the same sweet little girl she is in canon, but also has a split personality (named Red) with a higher kill count than the other Hinata Sou assassins combined. It's especially obvious when Red mentions liking Keitaro as a reason for Motoko to stop trying to kill him. After hearing this, Kitsune suggests Motoko just give up lest Red blow off her hands.

Luca

• The Story of Apollo, Daphne and Luca: An Italian Tragedy: Rosa is sweet, friendly, kind and innocent, but is also not afraid to use physical violence against people who misbehave and to show her more authoritative side in general.
• Too Much Too Much: The mild-mannered and kind-hearted Luca Paguro proves to be quite ruthless when he gives a lesson to Serafina Sforza after she refused to invite Giulia to her party for not being ladylike enough by giving her a perfume bottle filled with Giulia's sweat lying that it's a fine bergamot perfume given to him by Giulia's uncle.

Lyrical Nanoha

• Infinity: Shamal scares the bejeesus out of Nanoha and Fate in Chapter 20 for not taking it easy after the battle.
  • And Lindy. Sweet mother of god, Lindy. Especially in chapter 25, when her Mama Bear tendencies hit the stage.
  • Susanoo seems like a goofball most of the time, but if his family is in danger...

Marvel Comics

• In the X-Men: Evolution fanfic XXY:Evolution, where most of the characters are genderbend, John Grey (male Jean Grey) is a Nice Guy, Lovable Jock, and Cool Big Bro-figure to some of Xavier's younger students. But pushed too many times, he can use his powers for more offensive attacks. This worries Charlene Xavier (female Professor X) because when she first met 12-year-old John, his mutant powers first manifest as the result of the trauma of seeing his girlfriend (presumably Annie Richardson) run over by a drunk driver and caused him to develop a darker personality. Charlene had no choice but to erase his memory of the incident and placed psychic shields around the dark persona, but she fears the shields are slowly breaking down, likely foreshadowing his eventual transformation into the Dark Phoenix.
• Ultimate Sleepwalker: Sleepwalker is usually pretty level-headed. However, if you threaten his Heroic Host Rick Sheridan or Rick's closest friends and family, you will suffer.

Mass Effect

• Uplifted, a fic set in the middle of World War 2, features a young Wehrmacht NCO named Heinrich Fuhrmann. Heinrich is a soft-spoken, gentle giant, who frequently stammers, refuses to shoot wounded soldiers or the men trying to save them, and frequently finds himself duped by his superior officer, Joachim Hoch. However, whatever you do, don't try to shoot him. You might find yourself getting a bayonet in your chest or hit by enough molotov cocktails and machine gun fire to kill a small army.

Metal Gear Solid

• Stray contains an incident where this trope is applied to Otacon, of all people. It turns out that the quirky, tenderhearted, non-action anime geek can be dangerously resourceful when backed into a corner.

Miraculous Ladybug

• In Coffeenette, Marinette is widely regarded as a Nice Girl... that is, as long as she's well rested. If she isn't, a good cup of coffee will help restore her. But when she doesn't have coffee... well, her classmates do their best to either stay out of her way or just write their last wills for a reason.
• CONSEQUENCES:
  • MALICIOUS COMPLIANCE: As sweet and naive as Miss Bustier can be, when she witnesses Lila forcing a kiss on Adrien, then slapping him for daring to resist, she races over and rips her off of Adrien, dragging her all the way to the principal's office.
  • WORLD BEYOND: When Lila tries to convince the rest of the class that Hawkmoth is right to blame his latest terror spree on the heroes and that Ladybug and Chat Noir should just give up their Miraculouses, Adrien furiously calls her out, even swearing at her.
  • SUN'S WRATH also has Adrien snapping, to the point that he attempts to strangle Lila after being deakumatized. The same story has Ivan contemplating throwing Lila to A Fate Worse Than Death after she tries using Nino as a Human Shield, and Ladybug winds up decking Lila herself.
• Fashion Upgrade: Damocles realizes this is true of Tom. The principal believes the man is like a Great Dane, large and fearsome looking but ultimately harmless. He nervously realizes that the man is actually more like a Pitbull, gentle and loyal to those he loves but very vicious towards anyone who threatens them.
• Red For Fortune: The normally sweet Marinette gets especially scary when she confronts Adrien about a Mᴏᴅᴇ issue with a fashion spread supposedly inspired by the Lunar New Year, comprised of stereotypical outfits designed by his father, modeled entirely by white people in Yellowface, including Adrien himself. The fact that Adrien resorts to trite defenses of everyone involved rather than even try to comprehend why she's so upset ends up destroying the pedestal she put him on by the end of the chapter, and then gets her akumatised.
  Marinette: (throwing the magazine down on his desk) This is what's going on in here, Adrien. This racist pile of crap that your father helped produce.
  Adrien: (glances at the magazine and recognises the photos, before turning back to Marinette) You're upset over a fashion spread in Mᴏᴅᴇ? I don't see what the big deal is; I mean, none of it is lewd or anything. I guess this collection isn’t my father’s best work...
  Marinette: Oh, it's an awful collection; completely uninspired and cliché. But I wouldn't be half so upset if an Asian designer had been behind a shoot supposedly inspired by an Asian holiday.
  Adrien: There probably weren't any Chinese designers that were high profile enough.
  Marinette: Do you honestly believe the words coming out of your mouth? I can name three Chinese designers off the top of my head that have been members of Chambre Syndicale de la Haute Couture. There are tons of other Chinese designers that participate in Paris Fashion Week. One of them, Ms Min, even puts out a collection every year in honor of Lunar New Year. The Met Gala, you know, the premier fashion event in the world? It was teeming with work from Chinese designers last year - four of whom were featured in the exhibit! Your father has never caused such a sensation as Guo Pei's fox fur gown, and he sure as hell has never been featured in the Metropolitan Museum of Art. Gabriel doesn’t make art; if this is anything to go by, all he makes is racist garbage.
  Adrien: (stands up and glares at her) It’s not like he could control who Mᴏᴅᴇ asked to do this spread. They chose the person they thought had the best collection for what they wanted to portray.
  Marinette: Gabriel Agreste could have easily turned them down if he had the decency to see that what Mᴏᴅᴇ was doing was wrong. Of course, that would require him to realize that his collection was racist trash, and that Mᴏᴅᴇ clearly wanted to portray racist trash. (turning the pages over, with Punctuated Pounding) How. Else. Can. You. Explain. This? (finishes on a shot of Adrien) It wasn't enough that they whitewashed my culture, was it? They also had to deck their white models in yellowface. (glaring into his eyes) What made you think that this was in any way okay? How can you claim to be my friend and do something like this?
  Adrien: He's my father; I couldn't just say no.
  Marinette: Your relationship to him is precisely why you were the only one who could say 'no'.
  Adrien: (bitterly) You really have no clue about how wrong you are there.
  Marinette: I know that any other model or member of the production crew would have committed career suicide if they confronted him. Just as your father was in a position to turn down Mᴏᴅᴇ without consequences, you were in a position to call him out without ruining your future career.
  Adrien: You're crazy if you think I wouldn’t have faced consequences, Marinette.
  Marinette: What, you'd be grounded? Lose your video game privileges? No sweets for a month? Do you really care more about some petty personal comforts than doing the right thing?
  Adrien: 'The right thing'? This isn't some grand moral conflict. You’re overreacting.
  Marinette: Spoken like a truly privileged white man. Your father must be so proud.
  Adrien: Don't act like such a martyr, Marinette. It's not like you're some oppressed minority - heck, your skin is even paler than mine.
  Marinette: (lets out a harsh and bitter laugh before cutting it off and continuing to glare at him) You were right, Alya; white faves will always disappoint you in the end. (turns and walks out of the classroom, the magazine still in her hand.)

MonsterVerse

• There are a couple examples in the Godzilla: King of the Monsters fanfiction Abraxas:
  • Vivienne Graham isn't easily angered, but her temper was quite something when someone pushed her to her limit — and that was when she was still human! As a part-Ghidorah Artificial Hybrid, her temper is no less fierce, and she has more buttons due to her Trauma Conga Line and PTSD. Did we also mention her storm powers are fuelled by anger and hate?
  • San is a real sweetheart towards Vivienne, and he's at least tolerant and curious towards other humans, having always been the least malicious of Ghidorah's three heads even before being cut off from his brother heads and falling under Vivienne's influence. That having been said, God help you if you hurt Vivienne, who San dearly considers his sister. At one point, San takes control of his and Vivienne's shared body and, reminding everyone that he still used to be part of Ghidorah, he kills several of Alan Jonah's goons in an excessively violent and over-the-top manner that's designed to prolong their suffering for daring to psychologically torment his sister.
• Wild Child AU depicts a world where Godzilla essentially adopts Madison Russell after his battle with the MUTOs as he assumed her family had died in the battle, resulting in Godzilla and Mothra coming to see Maddie as their child. When Madison returns to civilisation during the confrontation with Ghidorah, she is briefly abducted by a group of soldiers with the idea of selling her to Titan enthusiasts. Although Maddie manages to escape, when Mothra learns what had happened she causes the kidnappers' helicopter to crash, the usually benevolent Titan outraged that those humans dared to harm Maddie.

My Hero Academia

• Ere we go, Pluz Ultra!: Inko Midoriya is as nurturing as she is unflappable. But when two villains break into her home intending to murder her, she calmly offers that they either fix her door and leave, wait for the police, or try their luck against the nine auto-turrets she just activated. Later, when she's made the supervisor of the U.A. dorms, she makes the most amazingly delicious confectionaries any of the students have ever eaten before warning them that if they attempt to peek on anyone in the bathrooms, her minor telekinesis Quirk works on both internal organs and extremities.
• The premise of Hero Class Civil Warfare is Midoriya using his analytical skills as a villain. The blurb sums it up best; Three days for Izuku Midoriya to show why they should be glad he's not a villain.
• In Juxtapose, Izuku is a sweet young man who wants to spend his life doing nothing but helping others as a Hero. He will also erase your vital organs from existence 10 g at a time, leaving you a cripple at best, if you threaten the lives of his friends. He has since refined this ability into "Scapel", which he can use to make precise incisions inside people's bodies. Sir Nighteye has also pointed out that he could easily slice buildings in half with a touch if he practiced even more. He later slices off Shigaraki's hands without hesitation when pushed into a corner.
• Hisashi Midoriya in Nine for All is a caring husband and father, acting as emotional support to Izuku after the latter learned he was quirkless, and when Izuku feared he failed his application to U.A., Hisashi takes his family on an outing to cheer the young boy up. Even when the mugger Jin Bugaigawara^note who in canon would become the villain Twice attacks them only for Hisashi to quickly disable him, Hisashi takes the time to ask Jin what happened what put him on that path, and offers to hire him as a lab assistant. But when Jin tries to protest that he isn't good enough, Hisashi grabs the man face and reveals he is furious that the first day he can spend with his family in three years was nearly ruined by a mugging and threatens Jin to either accept the offer or he'll burn him from the inside, all while spewing whisps of fire and quirk from his mouth to make him look draconic.

My Little Pony: Friendship Is Magic

• Applies to pretty much every pony in Ace Combat: Equestria Chronicles, but especially Fluttershy.
• The Assassination of Twilight Sparkle:
  • Celestia. Her being a kind and benevolent ruler doesn't matter once you've killed Twilight. Even if you're directly descended from her.
  • In the alternate version called Vengeance of the Star, Twilight is Forced to Watch as Spike (who she adopted as her son) killed before her eyes by assassins. As a result, she becomes Midnight Sparkle, and after capturing her would-be assassins, she makes them watch as she kills their families. Though it's later revealed that she faked their deaths.
• Changeling Courtship Rituals: Fluttershy might be quiet and easily startled, but her reaction to being startled is a swift right hook. Pinkie Pie proudly says she had a black eye for a week after throwing her a surprise party.
• Crystal Affair has Cadence. When she finds out that Shining Armor has been cheating on her, she actually tries to kill him! Fortunately, Spike is there to keep her from doing anything she'll regret.
• Did you hurt Apple Bloom? All-around Nice Girl Gabby will see to it that you need medical treatment as well.
• Fallout: Equestria: In the backstory, of the six Ministries created to fight the war, Fluttershy's Ministry of Peace was the only one working towards an actual peaceful resolution to the conflict. In the end, she was the one who destroyed the world by accidentally inventing the balefire spells.
  Steelhooves: In a world where not everyone is sane, it is the height of insanity to believe you could create a weapon so devastating, so horrible, that no one would dare use it.
• The portrayal of Fluttershy as seen so far in Friendship is Witchcraft.
• Cadence in The God Squad. She has 1) Made two stallions impregnate each other 2) wiped out a mob of rapists 3) Threatened to sterilize every zebra and thus render the species extinct (after they threaten Shining).
• Raspberry Beryl in A Hairier Problem: Rise of the Furball. She is usually rather meek, shy, and averse to talking with ponies due to her Dark and Troubled Past, but if you threaten to kill (or possess) an innocent pony or threaten (or Celestia help you, HARM) her pet phoenix she WILL try to rip the perpetrator to shreds with her dark magic. Prince Blueblood finds this out the hard way when he attempts to sabotage her trial by stealing Heliodor and causing the phoenix's emotional trauma to reach a point that his reincarnation cycle is shuffled up one year early. The guards barely reach him in time to allow him and Beryl one last tearful goodbye before he goes up in a burst of flame. In a rage Beryl completely freezes everyone in the room, verbally unloads on a scared shitless Blueblood, traps all of him but his snout in dark crystal, and is only saved from actually killing him with Apple Bloom's timely arrival and Cooldown Hug.
• The Immortal Game:
  • Twilight Sparkle, having been trapped inside her mind and forced to watch as her Superpowered Evil Side, Nihilus, tried to kill her friends, all while mocking her about it, finally manages to retake control during a critical moment of the Climax Boss fight between Nihilus and her friends. Nihilus begs Twilight for mercy, but Twilight coldly refuses and mocks Nihilus, even as the Elements of Harmony are used to destroy her.
  • Which is nothing compared to what Twilight does to General Esteem, the stallion who infected her with the Artifact of Doom that created Nihilus in the first place. After giving him a "The Reason You Suck" Speech and forcing his mouth shut to prevent any pleas for mercy, she proceeds to kill him in a brutally painful manner.
• This trope shows up in several stories by Kalash93:
  • In Reflections, Luna cares deeply for Celestia. She also won't let her sister run from her problems.
  • In Racer and the Geek, the protagonist is a very nice guy. He's also employed as a mercenary and won't hesitate to pull the trigger when it's called for.
• In Shell Shock, this is combined with Sadistic Choice and Break the Cutie in an extremely poignant way at the climax. "One more- give him one more! *BOOM!*"
  • In Welcome To The Brothel the protagonist takes time to write letters to his mother that showcase just how truly vulnerable and sensitive he really is. That doesn't stop him from being a highly effective warrior.
• My Little Denarians:
  • Rarity is a proper lady and sickened at the idea of violence. But when her friends are in mortal danger, she is the first of the group to start using human-made firearms. There is also Twilight Sparkle, who doesn't want to kill anyone but at her power remains extremely dangerous (At one point, when one of her friends is injured, she flips out with a banishment spell, sending several dozen cultists to the Moon... unaware that Earth's moon has no atmosphere).
  • There's also Cheerilee, who goes Mama Bear on an enemy stupid enough to take one of her students hostage.
• The Pieces Lie Where They Fell: Page Turner may be the Bearer of Kindness, but she can be pretty dangerous when she wants to be.
• Pony POV Series:
  • Fluttershy, as can be expected. Taken to logical conclusion when she snaps completely, getting corrupted in the same way as Princess Luna was and turning into the second Big Bad, Princess Gaia/Nightmare Whisper.
  • Later (or earlier, as it may be), during the Gaiden: Seven Dreams/Nightmares side story, Patch Took a Level in Badass, but still remains the goodhearted clown she's always been. However, her search for the fragments of the Rainbow Of Light leads her to the Pegasus Despot using the Blue Shard of Laughter to brainwash ponies and powering a city to become an Evil Overlord. He brainwashes her with it and makes her part of his brainwashed harem of mares, raping her repeatedly along with them. When she finally breaks free, she steals his fragment, shoots him in the leg, and leaves him to his Karmic Death at the hooves of his now equally pissed off and unbrainwashed harem. She goes back to being herself afterwards, but it shows she's not someone to push too far.
  • Dark World!Derpy is another example. She's still a kindhearted Ditz and probably one of the nicest mares you could meet, but she's the new Element of Loyalty and has spent the last thousand years walking nonstop around Discord's castle, making her very strong without using her new Super Mode. She proceeds to help the rest of the Mane Cast defeat the blackbirds that have spent the last thousand years trying to eat her daughter (who was turned into a muffin) and send them to Ponythulu's realm to be eaten. Later on, the Valeyard makes the mistake of spending the entire fight with him tap dancing on her Berserk Buttons. The result? She crosses the Rage Breaking Point and beats him to death after his Regeneration Template has been destroyed, ignoring his pleads for mercy.
  • Shining Armor is a Father to His Men and Reasonable Authority Figure who was Twilight's Cool Big Bro, but getting him truly clopped off is about as smart as royally ticking off Son Gohan. Not only will he use every ounce of his power to beat you to a pulp, his Thou Shalt Not Kill mentality tends to go out the window when he's in Tranquil Fury mode as the Diamond Dog that killed his Uncle in front of him found out the hard way. Even just getting normally ticked off resulted in him curbstomping a Mammoth Tank by systematically destroying all its weapons.
  • Princess Cadence is another example. She's the same nice, lovable person we saw in canon, but the two times she's been ticked off she ended up dishing out a Curbstomp Battle to cosmic horrors. And when she becomes Queen of the Changelings at the end of the Wedding Arc, she sentences Kabuto, Chrysalis' unrepenting sociopathic Mad Scientist, to several centuries (at minimum) sealed inside the sun, and completely aware.
  • God Is Good in this universe (with the exception of Discord, Morning Star, and some of the Outer Concepts), but ticking them off is a bad idea. Love God Venus is kind and all-loving, but the punishment she gave the pony that murdered her son (and in the process erased countless innocent beings from existence along with him) involved killing her, reducing her home to a smoldering crater, and then making it so no one (even the pony herself) could remember her name or what she looked like. Given the sheer amount of damage they caused, it's understandable, but shows clopping off a god doesn't end well.
  • The Alicorn Elders are among the most benevolent beings in creation and very difficult to genuinely enrage, but their wrath is described as being even worse than their Draconequi counterparts. The Father of All Alicorns stopped Venus' above wrath just long enough to inform his grandson's killer of the true magnitude of their crime...then told Venus Do with Him as You Will when they showed no remorse for their heinous crime. While what Fauna Luster is like hasn't been shown, it's stated fear of Her wrath is the reason no one is foolish enough to dare harm an unborn soul. This includes Discord and Nightmare Eclipse.
• In Princess Celestia Hates Tea, Celestia shows exactly why she is a Physical Goddess when wild accusations of being an imposter result in her entire staff, the Elements of Harmony, and her own sister trying to exorcize her. And the whole fiasco was over Celestia lying about liking tea to spare her sister's feelings.
• This is how Princess Luna is depicted in Progress. She is a kind-hearted alicorn, if socially awkward, but not many of the characters who get on her bad side remember the alicorn part until it's too late. Especially if her glasses are broken, as Angel has learnt.
• Quiververse: Quiver Quill is a meek, somewhat nerdy earth pony who's more than happy to keep to himself, and is genuinely nice to those he holds dear. Push him too far and there will be consequences. Spoiled Rich accused him of being a pedophile and slapped her repentant daughter Diamond Tiara while berating her. Quiver's response was to punch her hard in the face and then nearly strangle her to death.
• The adult fic Xenophilia gives us Lyra Heartstrings. She is calm, friendly, and reasonable, with a lot of sense of humor and a bit of snark. She is also a grand master of the Still Way, a unicorn telekinesis-based martial art, with enough control to Neck Snap you from across the street, without moving a muscle.

Naruto

• Catch Your Breath:
  • Kei may be one of the nicer members of Team Minato, but she won’t hesitate to rip your face off if you hurt someone she cares about.
  • Similarly, her mother quickly reveals that she has a near-bottomless pit of cold-blooded hate under her housewife exterior when pressed.
  • Minato is a nice, genial person who would rather avoid fighting if a situation can be resolved differently. But it won't stop him from ripping an opponent to shreds if he feels it's necessary. And woe unto those that make him angry...
  • Nagato, whose canon fate had been averted, is a nice, polite, even-tempered, and somewhat shy individual... with the ability to flatten mountains when pissed off. Do not poke with a stick!
• Naruto has two moments of this in Cry of the Raiju. The first time towards Jiraya when he discovers information about the Uzumaki clan that was kept from him his whole life. The second is also a moment of Tranquil Fury at the Kyuubi of all things.
  "I never wanted your power just as much as you never wanted to be within my fucking belly! Our fates sadly have seemingly intertwined, for what purpose can only be known for the future, however, I will not tolerate your behaviour as long as I am like this! I will not be told of my faults and my mistakes! I will not be told I am weak by the creature who himself is weak because he does not understand the meaning of compassion! So as long as you are in my fucking insides, I will expect you to shut up and curl in the fucking corner of your cage, do I make myself clear?!" The young Namikaze said coldly before he turned a full angle and walked away from the cage, leaving a silent, shocked, and aggravated fox.
  However the blonde paused as his fingers twitched with lightning and he turned and shot a large fully charged bolt of lightning at the fox's face, hitting him directly in his right side and striking a heavy blow on the beast's eye. This had cause Kurama to flinch back and growl in slight anguish as it covered his right eye in anger.
  "One more thing..." The temperature dropped around Naruto as he gazed back "I do not care if you hate me or want me dead, I don't care at this point, however let me give you one final warning..." His eye glowed a cold azure blue as he stared at the Kyuubi no Yoko. "I don't care if you are a god or a tailed beast, or even the first Hokage himself...you will not talk bad about my father and think that your word will not go unpunished. I will make your life a living hell if you want to boast and degrade the works of the dead and the sacrifices that they had to make in order to keep their world safe just a little more."
• In Eroninja, mild-mannered Shizune starts developing poisons after Naruto and Tsunade encourage her to follow her passion instead of trying to be a copy of her teacher. Tsunade is later disturbed by just how lethal some of Shizune's poisons are.
• Hinata in A Growing Affection is as sweet and kind as her canon self, though she does slowly become more assertive. She kills the immortal Madara Uchiha with a weaponized black hole Rasengan.
• Sai in Kitsune no Ken: Fist of the Fox is a polite, pleasant high school student who spends his time drawing and painting portraits, including painting his fellow students on his canvas if they ask him. But when four bullies destroy one of his paintings to intimidate him...let's just say Kakashi had to intervene quickly to stop Sai from killing one of them, AFTER he'd already beaten the four of them to within an inch of their lives.
• Hinata in Son of the Sannin keeps her gentle and sweet nature from canon, but there's a reason why she was named the best kunoichi in her generation when she graduated from the academy. Her major credentials for this include:
  • At the end of the Gaara Rescue arc, she's the first member of the cast who kills a member of Akatsuki, channeling electric chakra through her finger to make his heart explode.
  • Later she awakens the Tenseigan, and with the new powers she gained, her mother decides to step down as the Hyuga Clan head and name her as her successor. Her first official act is to abolish the Caged Bird Seal practice altogether, and she's quick to shut up the protests of the Main House members who try to complain about it.
  • During the Root arc, several of Danzo's minions kidnap Hanabi. When she confronts them, she demands politely that they hand her over or else. Then, one of the kidnappers makes the mistake of suggesting they use Hanabi as a living shield, and needless to say, it doesn't end well for them.
  • The climax of her character arc comes when she confronts Toneri Otsutsuki during the Fourth Ninja War arc. At this point, the man has given her plenty of reasons to make things very personal, including: 1) Trying to kidnap her as a child, 2) Attempting to kill Naruto several times, 3) Wanting to force her and her sister Hanabi to become his wives, and 4) Stealing the eyes of her late father Hiashi for himself. Says a lot that she still gives him one last chance to redeem himself by joining them against Akatsuki, but after he refuses and states his intentions to let the war rage on and eventually hijack the Ten-Tails' power for himself, she finally decides he's crossed the Moral Event Horizon, and battles him to the death, ending him with a chakra arrow to his chest that causes him so much pain that his final sound is a terrifying scream of agony.
• Team 8: Kurenai certainly thinks Hinata might one day snap under her father's mistreatment and abuse and kill him and herself.
• Uzumaki Naruto in White Rain is usually a happy, friendly, and goofy Hokage. When he stops being happy, friendly, and goofy, property values in Kusagakure drop in a hurry.
• your move, instigator (draw your weapon and hold your tongue): When Sakura first meets Namikaze Minato in person, he's seen as Uchiha Fugaku's more friendly counterpart as they plot to overthrow the Third Hokage, while Kushina describes him as her "sissy" husband. It's during the penultimate chapter when Minato is ruthlessly fighting Danzo while trying to find and rescue Kushina that Sakura is reminded why he's The Dreaded Yellow Flash outside of Konoha.

Neon Genesis Evangelion

• A Crown of Stars: Shinji is generally soft-spoken, calm, non-confrontational, and is also an Atoner who doesn't want to hurt or kill people. But he's also got a very primal, very violent side to his personality that comes out whenever his Berserk Button gets hit too hard. Harm Asuka and he will go from “I don’t want to kill anyone” to “I want to make them BURN!!” Much of his character development in the latter half of the fic deals with coming to terms with this side of his personality.
• Advice and Trust: Shinji is pretty quiet and meek. However when Leliel trapped Asuka into its body, he forced his Eva into a berserker, roaring rage, and shattered and tore to shreds its body.
• The Child of Love: It took a lot to make kind, non-confrontational Shinji snapping... but after his father Gendo nearly got Asuka killed, schemed to turn their baby daughter into a war weapon Shinji was most unhappy. Finding out Gendo had lied to him about burning all his mother's pictures was the last Straw. Shinji marched into his cell, called him out on everything, and said he wanted nothing to do with him anymore and that would be their final conversation (understand Shinji is usually terrified of his father).
• Evangelion 303: Shinji is the nicest guy on the base, and arguably the most dangerous because he's the type of person that will resort to risky, and often dangerous, tactics when under pressure. Case in point: that air-brake stunt he pulled during his duel with Asuka won the match for him, but also damn near got all 4 pilots killed.
• HERZ: Shinji hates violence and killing and he fervently wishes being a good person, husband, and father. And part of his definition for that means being there for his family and protecting them. And he will shoot whoever threatens them.
• Once More With Feeling (Crazy-88): Shinji is usually pretty calm and even glum, but when he faced Sachiel again and thought of everything happening again if he did nothing, he went berserker.
• The One I Love Is...: Shinji is usually nice and meek to the point of being a doormat. When he gets angry... he is scary. When his father meddled in his love life for his own purposes he coldly told Gendo if he interfered again he would refuse to pilot and the next Robeast could kill everyone as far as he was concerned (keep in mind he is terrified of his father usually). When an Eldritch Abomination hurt one of the girls he loved he attacked like an angry berserker. He even lashed out against Rei or Asuka when he was angry (and then he regretted it afterwards).
• Scar Tissue: Shinji is a wimp, and he tries to be nice, but he is really scary when he gets angry or he loses control of himself.
• The Second Try: Shinji, more so than in the original timeline as he's no longer plagued by crippling insecurities. Exemplified in his rematch with the 13th angel. He keeps calm during the fight, retains control of his EVA when Gendo tries to activate the Dummy Plug, and after Rei safely extracts the Entry plug from Unit 03, proceeds to use his prog knife to literally rip it apart before destroying it with repeated stabs in the core.

Omen IV: The Awakening

• Always Visible: As in the film, Delia here is a danger to Jo, but not because she does anything herself, but only because of her suspicious parents (and the fact that she was born with problems with the uterus).

One Piece

• Vivi in This Bites!. It was scary enough when she got angry at Cross for lying to her face about where the Rebel Army was (for good reason, and she apologizes for it later), but after escaping Rain Dinners and Smoker decides to try arresting the Straw Hats...well.
  Tashigi was downright quaking in her boots by this point, the woman who had fearlessly cut down an assassin not an hour ago looking ripe to piss her pants. Smoker's external reaction was one of stoic calm, but I could see the sweat dripping from his temple, and I'm pretty sure it wasn't from the heat.
  • What makes this doubly impressive is that, for the first time, Vivi invokes her family name as one of the 20 original world-creating kingdoms to do so.
  • Later Vivi fantasizes (to the point of drooling) over having a Buster Call initiated on a World Government island like Enies Lobby.

Persona

• In Persona: The Sougawa Files, the second Shadow the party meets, Shadow Ryouichi, is super happy and carefree almost all of the time. When he isn't? Run.

Pokémon

• Latias from Latias' Journey. She's depicted mostly as a gentle, somewhat timid, and fearful Pokemon. That changes big time in Chapter 5. After watching a bunch of evil bird Pokemon butcher a bunch of baby Flying and Bug types in Wing Fortress, she goes completely apeshit. The end result: a bunch of enemy Flying types lying in pieces in nursery, followed by a Psychic attack so powerful that it could best be described as a psychic nuke. That is followed up with an even more obscenely powerful Fire (or Dragon) attack that completely obliterates Wing Fortress and a large piece of the surrounding forest.
  • And killing the rest of the Pokemon she was trying to save.
• Asula in Pokéumans is terrifying when pissed. She is dangerously strong and has a wicked temper. Oh, and Glowing Eyes of Doom.

Pretty Cure

• Komachi retains this trait in The Pretty Cure McLaughlin Club. When she yells for you to be quiet, she means it.

Red vs. Blue

• In the fanfic Don't Tell Me Cause It Hurts, Donut has a bad reaction to anesthesia while undergoing surgery, and the resultant high results in him acting in his hidden resentments and giving harsh The Reason You Suck Speeches to Tucker, Wash, Grif, and Simmons, leaving them all with a bad case of Heroic BSoD.
• Murderer's Row: Donut is the Token Good Teammate for the prisoners and one of the only characters to have a working set of morals. He's also a vicious Combat Pragmatist who frequently wins fights against far stronger opponents.

Rosario + Vampire

• Tsukune in Stranger in a Strange World is just as much a Nice Guy as his canon counterpart. He also uses his Psychic Powers to make attempted rapist Kotsubo feel like he's on fire and when asked if he's going to "turn it off", Tsukune states "No."

Sherlock Holmes

• Dr. Watson in Mortality (along with every other relevant Sherlockian work by the author). Ordinarily, he's the nicest guy you'll ever meet. But you mess with Sherlock Holmes, and may the Lord have mercy on your soul, because John H. Watson will not. In one chapter, he's captured a criminal to interrogate, and he plays the Deadly Doctor trope disturbingly straight and delivers a pretty scary Badass Boast:
  “If your master’s actions destroy him whom I regard as — as the best and wisest man I have ever known… make no mistake that I shall hunt down, to a man, everyone who played a part in his destruction.” Uh-oh. We know how well things end for you-not well.
  • He most likely coldly murders the criminal when he reveals in having playing a part in Holmes's death while he begs for mercy. Yeah, not sure if it's a smart move to do that if a detective's dead.
  • Also, let's just say the end result for Culverton Smith is, well....unpleasant.

6teen

• 7teen: Fanfiction Series: Jonesy's father, Michael. Quite possibly the nicest guy you could imagine, especially considering all the hell he and his sons faced from when his first marriage ended to when he married his second wife. But if you dare insult his kids or his integrity in any way, you'll regret it faster than you can say "sorry".

Star Wars

• In Double Agent Vader, the generally easygoing Luke has his moments when pushed. At one point, he's invited to take the first shot at an effigy of Emperor Palpatine, and deliberately goes for a target below the belt, prompting Han to mutter that it's true what they say about the nice ones.
• In Star Wars: Lineage, Qui-Gon is presented as being his usual All-Loving Hero self, extraordinarily compassionate to every living being, and patient with his Sarcastic Devotee Padawan. But harm Obi-Wan or Tahl, and you will suddenly realize that this is a man who was trained by Dooku. He very nearly falls to the Dark Side when confronting Jenna Zan Arbor, and when a Well-Intentioned Extremist Jedi Master essentially Mind Rapes Obi-Wan, Qui-Gon's flat, cold response is as follows:

  " Sifo-Dyas can take a meditative retreat in the lowest Sith hell before I permit him to so much as touch my apprentice again."

• In "An Open Secret", Padme is willing to accept Barris Offee wants redemption and let her be her children's nanny. However, she also warns Barris that if any harm comes to them, her suffering will be worse than anything the Sith could imagine in a thousand years and Barris will only die when Padme finally allows her to.
• In Padawan's Return, when a time-displaced Ahsoka Tano reveals to the Padme of The Phantom Menace that Palpatine is the Sith Lord responsible for the invasion of Naboo, she requires the aid of Padme's handmaidens to stop the young Queen basically charging off to try and kill Palpatine with her bare hands.

Stargate SG-1

• Plays a key element in Daniel Jackson's personal development in What You Already Know; he might not be a trained soldier, but if anyone pisses him off after his psychic powers manifest, he will do some serious damage, ranging from just playing practical jokes on Jack to blowing up the contents of Kinsey's garage just because he can.
  • While Daniel's ruthlessness has been shown in the series in extreme circumstances, it's almost fascinating to see what Oma Desala does once Daniel gives her the chance; after Daniel forces Anubis back into his mortal form, Daniel calls Oma down to finish Anubis off, and she completely incinerates the Goa'uld's once-again-mortal body, to the point that even Teal'c and Bra'tac are disturbed to see the ash that was once Anubis when they find the ship.

Super Mario Bros.

• Driad in Clash of the Elements. The outer guardian of the Frozen Palace learned this the hard way when Driad regained his memories of his life as an outer guardian and briefly returned to that form to combat him.

Supernatural

• In It's All in the Details, while Gabriel has been established as the 'nice' Archangel, he's still dangerous enough that Abaddon decided it was easier to flee than continue trying to fight him.

Tengen Toppa Gurren Lagann

• Nia in Tengen Toppa Gurren Solvernia, in her first fight, she tries hard to talk the ganman who is striking the village to stop, seeing no sense in the destruction, but when he threatens to kill everyone in the village, Nia snaps and reduce him to scraps.

Total Drama

• A Codette World Tour: Bridgette is a gentle, compassionate, and fundamentally good-natured girl known for her kind, sweet, and caring nature, but when she discovers Alejandro's true nature as a cruel and ruthless bastard who cares only about winning, has hurt all her friends, and sees her as just a shallow, easy harlot for him to use and throw away, she is utterly furious and becomes completely determined to prevent him from winning the season. Even Alejandro himself was terrified by how enraged Bridgette was when she snapped at him.

Touhou Project

• An age-regressed Reimu in the Gensokyo 20XX series is described to be a sweetheart, despite being mentally ill and suffering from poor health, however, when pushed, she stabbed someone with a pair of scissors.

Transformers

• Autobot Academy: Bumblebee is one of the nicest, friendliest students at Autobot Academy. However, upon learning that Sari Sumdac tricked him into fighting off law enforcement coming after her, he doesn't even hesitate to knock her out and bring her in once she starts begging him to keep helping her. Even said law enforcement is shocked.
  Wes: Ok, wow, you Autobots can be SPITEFUL when you're angry!

TRON

• The fandom is more or less in agreement that this trope is in play for Alan Bradley. A quiet, reliable programmer in coke bottle glasses who is never unintentionally rude, he is Tron's creator, and Programs in this universe reflect the best and worst of the human that codes them. Translation? Fanbase realizes that meek, fatherly dude has a Rinzler flavored Dark Side!

Undertale

• Frisk in If We Fall Down. They have a Love soul, they're a friendly and good-natured kid when they open up, and they DO want to get the best ending for everyone... but that doesn't mean you should cross them. They have a violent temper, they take pleasure in beating down on bullies, and they REALLY don't like being attacked and antagonized nonstop. When under serious pressure and anger, they were fully willing to write the highly antagonistic Undyne and Flowey off as bad people and leave them Killed Off for Real, if not for Chara.
• Asgore in TS!Underswap. Even though he's a warm, fatherly goat man, he'll still fight you near the end of Ruined Home to keep the other monsters from getting your SOUL. He also won't hesitate to kill you on a Genocide run, with stronger attacks to boot.

Worm

• Co-op Mode: As of the Grave Lord omake, James is revealed to be capable of being between this, Good Is Not Soft, and Knight Templar. In that alternate possibility, alone and without Taylor, James ends up single-handedly disabling and capturing each and every hero in Brockton Bay while scaring the villains badly enough to keep away while he does it to save Taylor. However, in the omake, he doesn't avert Good Is Dumb for forgetting that he could've done it with less violence.
• Hope from Hope Comes to Brockton Bay is an archetypal All-Loving Hero, willing to listen to and accept all manners of people no matter their conduct. She's also perfectly willing, among other things, to hold down an Ax-Crazy serial killer for summary execution, even if she thinks it Dirty Business afterwards.

Warhammer 40,000

• Glory Or Death: The Crimson Crusaders are cheerful and humorous. They are also ruthless in fighting the enemies of the Imperium.
• Nobledark Imperium: Pre-Necron Nemesor Zandrekh was just as benevolent as he is now, if more coherent, but it's specifically noted that this did not make him harmless — Necrontyr politics were insanely cutthroat, and Zandrekh could afford to be so nice because he was also a brilliant strategist who could make people pay for underestimating him.

Yu-Gi-Oh!

• (æ)mæth has a Breather Episode in Chapter 3 where Masumi sees a student counselor to try and find an answer for the nightmares she's been having. This counselor is nice, charming, and tells wonderful and engaging stories over her mother's home-grown tea. In Chapter 10, it's revealed her Psychic Powers are the source of those nightmares, and things go downhill fast.
• In the Yu-Gi-Oh! GX Spirit Caller fan fiction, the protagonist Kaigen Kou is usually calm and slow to anger, but bullying or mistreating his friends releases a terribly ruthless and somewhat psychotic side. It's a bad idea to bully his friends but sully the reputation of the woman he loves and you'll find yourself beaten half to death and inches away from being LIT ON FIRE.

Other

• A common theme in Vathara's works is that she believes "Beware the Nice Ones" is a contradiction; if you're nice, you can't be dangerous, and if you're dangerous, you can't be purely nice. "Nice" people need "less-nice" people to protect them because the idealism that builds thriving societies is incompatible with the actions necessary to protect those societies from harm. Any paragon in her works who attempts to do both has to either accept that darkness as part of themselves or go stark staring mad.
  Katara is not honest. Katara is sweetness and confidence and "we're going to help Aang save the world!" Until she runs into something she doesn't like, at which point the Sugar Queen cracks, and a lot of nastiness oozes out. ...Yeah. That relationship is going to end so well. I think I'll take my chances with Azula...
• Matthew Streika. Definitely one of the nicest, most decent people in a book full of things trying their very hardest to kill almost everything else, and is trying his best to make sure said dangerous things stay well away from his hometown. All he really wants is to make sure innocents don't get involved, and protect his friends. He does not go looking for trouble. That said, do not mess with Matthew. Because when you manage to get him into a fighting situation, he is utterly ruthless and ferocious in a fight, not even minding his own pain until all hostile forces are either running with their tails between their legs or dead.
• In any Adventures Of Blinky Bill fanfics written by Canzet Yote, it is NOT a good idea to piss off Shifty Dingo or Nutsy.
• In Passing Days, unlike the original Fujimaru Ritsuka from Fate/Grand Order, many antagonists find out firsthand why Vy shouldn't be messed with. Flauros!Lev gets a Gandr to the face in the America Singularity from her rage over the Incineration killing her family, BB gets Flipping the Bird and a scathing "The Reason You Suck" Speech over her "help" and insults to Robin in the SE.RA.PH. event, and Wodime gets a No-Holds-Barred Beatdown in Atlantis for his role in helping the Foreign God. As much as Vy is kind, she does not play around when her loved ones are threatened.
• In one particular route of Retrieving the Amethyst, a Henry Stickmin Series fan fic, Ellie stops being calm and is very pissed off at Dmitri after he murders Tony and Alica for helping two convicts escape and for ruining the reputation (again). Even Henry was really afraid of her.

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