Ah! My Goddess
- From the fic Ah! Archfall!: you can do what you like to Jago, but you insult or threaten Lind, their unborn child or either of his Archs, and the very least he'll do is beat you senseless. And if you force him to summon Papa Jupiter to do it, he WILL kill you.
Aaahh!!! Real Monsters
- In An Ounce Of Prevention, Slickis is so angry upon learning that Zimbo's taunts caused Ickis to develop bulimia that he grows to full loom and threatens to squeeze Zimbo to death if the bee monster ever does anything like that again.
Attack on Titan
- Corporal Levi in My Child, to his and Mikasa's unborn child. In order to save the child from dying in childbirth, Levi makes a deal with the demon that has been hounding him the whole story to sell his soul for their safety. The baby is born healthy and safe, but Levi is dragged to hell to be tortured by the demon for all eternity in exchange. However, the knowledge that his son Rivahn is safe is the only thing that keeps him from regretting it.
- Avengers fanfiction has a ton of examples where Hulk gets mighty protective over Clint/Hawkeye, but none more so than Big Green Guardian Angel. The biggest scene in the one-shot was when Clint, after accidentally exposing the scars on his torso, explains that he got them as a kid, causing Banner to Hulk out right then and there. As if that wasn't "aww" eliciting enough, Hulk stopped his rampage enough to trace Clint's scars, whimper a little, and proceed to destroy everything in sight as a result of his rage.
- Hawkeye becomes this to a de-aged agent Coulson in this story.
- Note that this story is an inversion of the Fandom-Specific Plot in Avengers fanfic where all the Avengers get de-aged and Coulson has to babysit them. Such stories usually depict Coulson as the Papa Wolf Team Dad.
- Loki, of all people, becomes this to his adopted daughter in the fic Mischief, Lies, and Other Hazards of Parenting and its sequel, Thor's Days. In the first he practically bolts to the park where she's having her birthday party when he thinks its being attacked by Dr. Doom (it wasn't), and in the second he almost snaps her scout leader's neck when she's injured due to said scout leader's incompetence (Tony intervened that time). And then in one chapter, Natasha comes to him and makes a hint that Clint might go near the girl. Loki's response is scary.
Loki: I will, however, show no mercy to anyone, and by anyone I mean your dear Agent Barton, who chooses to strike at me through her.
Natasha: So if Clint takes Kara, you'll kill him?
Loki: Has my dear brother ever told you how he and I would sneak into the orchards of the goddess Idunn when we were children? Those apples, which I was so very good at stealing, grant whoever eats them a very long, very resilient life. If your little friend does anything to Kara, I will find a way into Asgard and strip Idunn's orchard bare. I'll cram them down his throat and save enough for you, so you can watch as I torture him for eternity. No matter how much either of you beg me to kill him, he'll live through every length of gut ripped through his flesh, every severed limb, and every drop of acid spilling into his eye. Now is my meaning clear?
Back to the Future
- In the fic Back to the Future Prequel, Marty is kidnapped by a vengeful enemy of Doc's, who throws him into an icy lake to drown. Doc subdues the physically bigger enemy and swims two hundred feet to save Marty.
The Black Cauldron
- In Growing Family, Jeremie reacts violently to his and Aelita's daughter Anya's request of going to Lyoko and when Odd muses on teaching her to be a troublemaker, threatens to leave him in virtual limbo if he corrupts Anya. Odd reacts with appropriate terror.
- In To live again if you mess with Annie, Gideon AND Rossi will end you. In general - you don't go after the BAU's children unless you have a death wish.
- Harry Potter And The Invincible Technomage:
- Tony Stark becomes this to his adopted son Harry in this Harry Potter/Iron Man crossover fanfic. It is also demonstrated that many of the heroes feel this way toward their allies' children.
- Thor gets a Moment of Awesome (that doubles as a Funny Moment) when the Ministry of Magic tries to take Harry away from Tony: Thor breaks in and calmly warns the Wizengamot that voting for taking Harry away would cause Thor to tear down the building and break every single bone of every member of the Ministry. Harry then gets him to amend it into only tearing down the building and breaking the bones of everyone who voted yes (the rest of the Ministry people are innocent, and the Aurors that would try and fail to stop him are merely doing their job). The Wizengamot promptly vote to leave Harry with Tony.
- Child of the Storm has a number of these, most notably Thor. He has so far terrified the Dursleys and only narrowly restrained himself from incinerating them (because what Tony had planned was more humiliating and excruciatingly painful), Snape, explaining exactly who he is, what he is capable of and what he will do if Snape even looks the wrong way at Harry and sent Gravemoss running for his life with one shot after Thor caught up with him (because Gravemoss had orchestrated Harry's kidnapping by the Disir. While Harry managed to Indy Ploy his way out of trouble, Thor was Not Pleased). Gravemoss, bear in mind, is a Physical God who had previously killed Sif with minimal effort (she got better), regarded losing an arm as a mild annoyance (he grew it back) and tanked Harry Dresden's Death Curse, which had blasted him over 500 miles from Paris to the North Sea, as well as being a mystical powerhouse on par with Loki. Thor sent him running for his life.
- Odin. He may have made mistakes, but holy crap, you do not want to be in Thanos' shoes when the Allfather catches up to him, not after what happened to Loki (while Loki's madness was his own and, as acknowledged by Loki himself, his responsibility, Thanos was not exactly kind to him).
- In a direct example, when Chthon, an Elder God, threatens his family in chapter 77, the response is a simplified Facebuster.
- And in the sequel, when the Red Room kidnap Harry, Odin responds by unleashing The Scourge of God on Russia.
- Afterwards, the Council Elite of Skyfathers, each one nearly as powerful as Odin, are considering binding or killing Harry because of the threat he potentially represents as the Dark Phoenix, he goes to the meeting and makes it entirely clear that if they want to lay a finger on his grandson, they are going to have to go through him to do it.
- The Avengers in general are this to Harry, even after he becomes more than capable of looking after himself. Loki does not take kindly to the thought of his nephew being interfered with, warning Albus Dumbledore that while he, Loki, notes and approves of his plans, he had better tread carefully where Harry is concerned. Clint treats Harry like a little brother and when he's kidnapped, says that he wants to teach Harry to shoot. And he will. With a practical demonstration. And the Hulk... well. He likes Harry. As Bruce puts it, 'We will find Harry. And Hulk will smash.'
- And after Harry has a painful run-in with the Red Room in the sequel, Loki's primary response, aided by Clint, Natasha, and Bucky, is to quietly and methodically track down and murder every single Red Room Agent they can find, draining the knowledge of their senior officers from the mind of each Agent so he can work his way up their chain of command, then back down again.
- Albus Dumbledore is this to his students. Hurt one of them and you will find out why this man is considered the most powerful wanded wizard on the planet and feels comfortable dropping extremely politely worded fuck-you's to the Merlin of the White Council.
- Magneto. He loves his children, and while he has at least nominally reformed, he is an Omega Class mutant and everyone with a brain is absolutely terrified of him, and for damn good reason.
- He also extends this attitude to Harry, who he regards as a kind of adjunct grandchild on the grounds that his daughter Wanda is Harry's godmother, would have taken him in and raised him as her own if circumstances had been different, and is currently the closest thing Harry has to a mother. Certainly, he name-checks what the Red Room had done to Harry as well as what they had done to Lorna as his motivation for unleashing hell on them.
- He further extends it to Harry Dresden, Wanda's apprentice and boyfriend/his potential son-in-law, as Quintus Cassius found out the hard way.
- We don't know much about Stephen Strange, prior to his Origins Episode in chapter 20 of Ghosts of the Past. But one of the things that is widely known is that when the White Council came for a thirteen year old Wanda, judging her too dangerous to live after her powers went haywire, he challenged them to a duel. All of them. This is an organisation numbering about two thousand Wizards, the most powerful 1% of wandless practitioners on the planet, led by the seven members of the Senior Council. These are seven wizards, all centuries old, who can do fun things like pull satellites out of orbit and drop them on your house with pinpoint precision, while the Merlin can stonewall an army of Red Court vampires and Outsiders with a single on the fly ward. Combined, they are a bona fide hyperpower and less a collective of magical beings, more a force of nature, one entirely unfazed by the prospect of taking on Dumbledore, Charles Xavier, and Magneto, at once. But when Strange threw down the gauntlet, they backed the hell down. Part of that was probably Strange's sheer reputation... but he earned that reputation. All told, one does not mess with the student of the Sorcerer Supreme.
- When Coulson recruits Harry Dresden to track down the veidrdraugar and their Master, Dresden is reluctant because he knows very well that he's out of his depth - one of these creatures nearly ripped Loki's throat out, after all, and their Master is an Omega Class threat, never mind the Darkhold, which said Master possesses. Then he finds out that they killed children and takes the case, harshly telling his apprentice, Bruce Wayne, to get out (because Bruce is a bit too nosy for his own good and would end up dead or worse if he got involved). Dresden does not tolerate children being hurt or put in danger.
- A few chapters later, Gravemoss utterly dismisses Dresden and rips out Sif's heart with his bare hand. Dresden responds by unleashing his Death Curse. This is under Paris. A few moments later, a vast column of fire about a thousand feet high erupts over the Paris skyline and Gravemoss lands in the North Sea, somewhere off the east coast of Britain. And as a bonus, he incinerates several dozen of the veidrdraugr as a side effect.
- Even Lucius Malfoy counts. He is as evil as they come, a fully fledged Magnificent Bastard who has a somewhat Dalek like attitude to muggles (though he considers torturing them to be beneath him) and murdered Harry's maternal grandparents in cold blood. But as Baron Von Strucker found out, threatening his wife and son is the last thing you will ever do.
- In the Ultimate Re-Imaginings, Clint is this towards Joey as he once nearly killed the boy's actual father for putting him in the hospital and breaking his arm when Joey had been twelve.
- John Winchester in Supernatural/The Matrix Hunting Series part 3 - Hunting and Saving.'' He kills three vampires to save a little boy called Tom Anderson, thinking that he'd never be able to live with himself if he let the vamps live to kill more kids. That if he did it'd be like watching them kill Dean and Sam while he watched and he'd never let that happen.
- Do not mess with Dante's children in Dante's Night at Freddy's or its sequel. He will gouge a carousel out of the ground and drop it on you if he can't find anything bigger.
- Adopted Displaced, a My Little Pony: Friendship Is Magic multi-crossover series: All of the adoptive fathers and honorary uncles (and other males in the new families) in its various installments are highly protective of their adoptive Equestrian children, even after they've shown they've become strong enough to take care of themselves.
- Betelgeuse is this for Lydia in the Beetlejuice/Danny Phantom crossover Say It Thrice. Following the events of the movie, he - regretting certain past actions - effectively adopts her as his protectorate, and by the time of the fic they are Like Brother and Sister. He calls her "my girl" and has a tendency to go ballistic if anyone even thinks about hurting her.
- Wonderful!: Danny is this to his daughter Taylor. When a psychopathic mass-murderer threatened her, Danny tackled him.
- Jack Kenway in Harry Potter and the Grand Trainer Tournament towards his adopted daughter Jasmine. When she was seven her parents were killed during a rally protesting Kanto basically ruling over Johto. That night Jack asks Jasmine what she wants and she says she wants Kanto to hurt. Jack proceeds to declare war on Kanto, ending with his discovering a lost Pokemon Art and blowing up the Kanto Pokemon League. To repeat... he started and won a civil war because the daughter he'd just adopted was crying. No one messes with Jack's little girl.
- Remus has become this for Harry. When Lockhart tries to take a picture with Harry and wraps his arm around him Remus throws him to the ground and makes it VERY clear that no one touches his adopted son.
- A Man of Iron shows Tony deciding to become this for Jon Snow, as someone has to take care of the kid and Ned simply doesn't do enough for his cousin's standards. Do not think he's unable to get serious when it's important: he outright verbally demolished Catelyn Stark when she threw an hurtful comment towards Jon and called Ned out on his shortcomings as a father doing nothing to protect his son from his wife. Though he thinks of himself as being Jon's uncle rather than his father.
- In the RWBY/Marvel Cinematic Universe Fusion Fic In Shades of Red and Gold, Tony becomes this to his daughters Ruby and Yang, giving a "The Reason You Suck" Speech to Christine Everhart after she asks if he feels guilty that he's raising them using money from weapons development, and his primary motivation for creating the first suit is to escape so he can see them again.
- The Death God Alliance shows Hades' very measured and restrained reaction to his son Nico's disappearance - which involves damning evidence against the House of Life - as declaring war against the magicians. Oh, and he also enlists his brothers Zeus and Poseidon's help to ensure the war would be an one-sided slaughter. Poseidon also has shades of this, agreeing to help Hades in part because he had a history of Egyptians causing misfortunes to his children.
- In A Child Avenged Harry reacts very poorly to Director Fury kidnapping his five-year-old godson Teddy to try to threaten him into joining the Avengers Initiative.
Harry: I'm leaving, but know this: If Teddy transforms this month because of your careless actions, you will face the consequences, and if you ever even think of touching him again, I will paint the world red with the blood of your Agents, and I'll leave you to fucking watch, Fury.
- In The Bridge, Godzilla Junior becomes the mentor to a filly named Chibi Moon who has a lot of potential as a unicorn but lacks control until he became her sensei. When a brainwashed Starlight Glimmer is shown to have kidnapped and locked up Chibi Moon, Godzilla Junior flies into such a warpath he overpowers Starlight's cutie mark removal spell and Nightmare's attempt at possession by sheer willpower alone.
- In From Fire, Professor Xavier feels his new pupil Harry's psychic distress and goes to help. When he finds Lord Voldemort determined on destroying the boy's mind, he becomes quite upset and engages into a psychic brawl with the Dark Lord while protecting Harry's mind from the fallout.
- Despite his initial reservations about adopting Izuku, Hisashi Midoriya proves to be this in Neither a Bird nor a Plane, it's Deku!, fiercely defending Izuku from Detective Shitsugen when the latter said that someone should get punished for Katsuki's grievous injuries. As Firestorm, he's even more protective of Izuku, threatening to turn all of Mt. Fuji into a pillar of salt if it meant killing the Ultra-Humanite after the Villain seemingly blasted Izuku to his death. His sheer fury was enough to give even All Might pause.
- All Might, who took Izuku under his wing, isn't lagging behind either. When the above-mentioned event with the Ultra-Humanite happened he was sorely pissed, but when the USJ Arc happens Izuku finally meets a threat that is capable of hurting him (the Noumu) and what All Might does when he finally arrives and sees Izuku beaten to an inch of his life and a nanosecond away from getting his spine snapped in half à la Bane is to tear the Noumu to pieces and attack Tomura Shigaraki in such a brutal fashion that only the timely support of his fellow Villains prevented him from dying right then and there.
- In the Crack Fic A Charmed Life after learning that Shinigami can die, Light becomes one for Ryuk much to his Shinigami's amusement.
- In A Cure for Love Matt is one for V and Mello and Light is one for L:
Matt: I know you're Kira or whatever... this is me impressed. Doesn't change the fact that if you start any funny business with her, I'll shoot you through the fucking wall. I'm quicker than you and your little Diary of Death. OK?
Light: It was you, wasn't it? You fucking tried to kill him!
V: I'm sorry, Light.
Light: Not going to cut it, V. I thought that you didn't want to kill L.
V: I don't.
Light: If you touch him, I'll kill you. I'll kill all of you.
- Light/Kira becomes this for L and the Wammy's Kids in the Death Note fic I Won't Say:
I will also keep the Death Note
where I can reach it whenever I need to, because I will need that power to protect you and our orphans. But... would you, and could you, perhaps, consider... combining Kira and L's powers?
L: What, as in, 'Quit killing, or I'll set Kira on you'?
Light: Yeah, pretty much like that.
Devil May Cry
- AU Devil May Cry fic "Like Father, Like Son" has Dante exhibiting his demonically-protective side when he finds his son Nero injured courtesy of a police officer with temper problems, and when Nero is later threatened by members of the mafia. The second time Nero gets threatened by the son of a mafia head, a partial Devil Trigger sends the man leaving with tail between legs. And when Dante finds the demon Baul, who had all but put Nero near Death's door... Cue Unstoppable Rage and Roaring Rampage of Revenge with a dash of There Is No Kill Like Overkill.
- The Discworld fic Hyperemesis Gravidarum sees a new development for the Guild of Assassins. Several years after the first women officially graduate, inevitability sees a trio of pregnant Assassins. And it's at a time when a desperate gang with nothing to lose are targeting Assassins. One in particular. The murder gang discover Lady Assassins are Mama Bears when pregnant. It can only end one way for the terrorist gang. Especially when Mama Bear is assisted in the end by the soon-to-be grandfather of her child, who realises that this time his Assassin daughter might just conceivably be taking on too much. He steps in to fight for her. And wins.
"Nine hundred and ninety times out of a thousand, your grown-up daughters are big girls who don't need you around any more." he said. "But on the thousandth time, a man had better be there for his girl, because she really will need him."
"Good." Johanna said, feeling five or six again.
- Roy DeSoto in this fic series. In one of the fics, he readily battles with a bear to protect his young son and John Gage. And though John is like a little brother to him, there's also an element of parent-child love in their relationship, and it's even lampshaded by Roy's son that Roy acts like a parent protecting his young when someone tries to hurt John-which happens quite often during the series.
The Fairly OddParents!
- In Never Had A Friend Like Me, Norm gets rather attached to his current master, an eight-year old Shrinking Violet named Amanda who couldn't make a selfish wish if she tried. Anti-Cosmo and the Head Pixie put her in danger as collateral damage during a revenge plot against Timmy. Norm doesn't take it well. He ends up trapping the anti-fairies and pixies under butterfly nets, giving them a clear outline what it means to tick off a powerful magical entity with no limitations on what he's allowed to do, and trapping their entire species in their homeworld with no way to return to Earth or Fairy World without outside help. And made it clear that this was being merciful because Amanda wouldn't like what he wanted to do to them.
- Before that moment, he had given Amanda's emotionally Abusive Parents terrible flu for making Amanda cry on Christmas.
- Helena's father in Frozen Hearts. While he fell into despair and alcoholism after losing his job at the castle as part of the staff reduction to keep Elsa's powers secret, he springs into action to protect his daughter from someone who tries to take advantage of her, and Helena recalls that at that point, he seemed to be his old self again. Unfortunately, he gets fatally stabbed in the process.
- The most common idea for parental Roy/Ed fanfics.
Girl Meets World
- In Harry's New Home, Snape will go to any lengths to protect his ward Harry, even if it included breaking rules or facing the Dark Lord and Dumbledore (if necessary) to do it. For that matter, Dumbledore does not like seeing any of his students harmed in any way, especially if it's Harry. His Berserk Button is pressed when he finds out Umbridge used a Blood Quill on Harry and in the prequel, he gives a casual warning to Snape who earlier in a fit of rage slapped Harry. All in a cheerful tone and a benign smile.
Dumbledore: You do understand that if you ever, ever again strike a student in so brutal a fashion, you will not survive the night, correct?
- In 3 Slytherin Marauders if you try and hurt Harry, Snape will end you... that is if Tom doesn't do it first.
Axis Powers Hetalia
- In response to the kink fill "Finacial Crisis Gangbang" where most of the main cast rapes America, "Use Your Fist Not Your Mouth is an AU fic where England and France not only not participate in it, but fight off his attackers to stop it from happening.
- In Just about any fic where America is the parent of the personified states, he will be this trope for them. This goes double if he has a Love interest and said Lover is in danger.
- The fic Warden portrays Tinkerbull (a tiny winged-bull creature) as this. It was inspired by someone pointing out how strange it was that Tinkerbull could survive on Alternia.
- Inspector Gadget has always been a bit of a Papa Wolf, but in Re Initiated, we really get to see his protectiveness come through. This is especially apparent when Penny is abducted and injured by Charles Freymore, and Freymore tries to trigger a SelfDestructMechanism to keep her from escaping. Gadget makes it very clear that he will save his niece, and that he'd die in the process if that was necessary.
- This comic shows what would happen if Georgie and Pennywise became friends. Pennywise may have decided to befriend Georgie rather than eat him, but he's still a monster as Henry Bower and his gang find out when they decide to mess with Pennywise's little friend. A follow up shows Pennywise turning on the Abusive Parents of Derry.
Jojos Bizarre Adventure
Kung Fu Panda
- The Vow (an Alternate Universe Fic of Lord Shen's life) provides several examples.
- Shen's father Lord Goa is a fair and calm ruler, but should his son or honored guest Lady Lianne put into immediate danger, he can be as ruthless as his son. After Shen is banished from Gongmen for his crimes and Lianne is demanded to return to her distant father Lord Chang who would continue pressuring her into marriage (with her having a broken heart due to her beloved Shen's actions), Goa prevents Chang from harassing Lianne for the rest ten years of his life.
- There's also the canonical version of Po's father.
- Lianne believes for a long time that her father cares nothing for her safety, else he wouldn't have tried to marry her off so emphatically or sent her to live with strangers for a year after an argument about the quality of suitors he foisted onto her. However, when she returns to her birth home after three decades of absence, her uncle Hong reveals that when Chang heard about Shen's return and the subsequent imprisonment of Lianne, he wanted to do everything needed like calling upon every favour he owed, summoning every general and friend or even seeking an audience with the Emperor himself to raise an army and storm Gongmen City in order to rescue her. The only reason he didn't do this was because he suffered a stroke in his stress.
- In the epilogue, Shen himself becomes this after he warms up to his and Lianne's son Zian, being as determined as Lianne to keep him safe.
The League of Extraordinary Gentlemen
- Skinner, Nemo, and Jekyll all have a tendency in this direction in The Private Diary of Elizabeth Quatermain. Jekyll has (eventually) his adopted son, Nemo has his foster daughter, and Skinner has his niece.
The Legend of Spyro
The Loud House
- In the AU fic Knocked Up, Megamind saves a pregnant Roxanne from an extremist group intending to do their unborn child harm. And then, after the baby is born...
Megamind: If anyone harms even a single hair on my daughter's head, or has a clear intention to do her, or her mother, harm, they will be obliterated with whatever weapon I can get my hands on quickest.
My Hero Academia
- Conversations with a Cryptid:
- All For One, in his own villainous, murderous way—as the villains that kidnapped Izuku found out to their detriment. He also previously had the children who bullied his child disappeared and experimented on beyond recognition. And he has plans for Bakugou...
- After All For One escapes from the prison and believing he was going to harm Izuku, All Might is ready and raring to confront the latter, even if it meant his possible death, all so he could buy some time for Izuku to escape.
My Little Pony: Friendship Is Magic
- Pony POV Series:
- Discord's Father Havoc, Anthropomorphic Personification of Mass Hysteria, is an odd case. He's an Abusive Parent, and He'll mock his children if they get beaten up by people defending themselves from them. However, any who harm them unprovoked will know His wrath.
- As shown in the 7 Dreams/Nightmares side stories, Sweetheart's husband Teddy was this. When some corporate thugs tried to harm their family in order to intimidate their friends out of activating the world changing spell, he put them all in the hospital. And after the disaster caused by said spell failing, he fought off a group of smirughs that attacked the family when they were seeking refuge.
- Lord Tydal in The God Squad takes Papa Wolf to the extreme. Tydal tells his group about how he raised Celestia and Luna when they were babies, after their Mother (the creator of all things) dumped them on him. When Commander Hurricane and the pegasi army march up to Tydal's Keep, demanding the foals, Tydal tells Hurricane that two other armies (these being unicorns and earth ponies) beat him there. Tydal then reveals hundreds of severed heads before delivering this speech:
Celestia and Luna are my sisters and under my protection. Three times Equestria has come to my door... the next time I see a flick of a ponys tail my army will march upon your pathetic little country and I will raze it to the ground. Your stallions will be slaughtered, your mares used for our pleasure and your foals sold as slaves. I will burn your forests and salt the earth so nothing will grow again. I will burn the skies and cover the lands in darkness. I will personally come to your little Cloudsdale and I will rip it down from its high perch and crush it under my hooves. And only when this is all done will I finally come for you and your fellow rulers
and then your agony will begin. I will visit death upon you a thousand times and still not let my brother the Reaper claim your souls. That is only a taste of what I will do if you EVER THREATEN MY LITTLE SISTERS AGAIN! So... in a word, Commander... run."
- Tydal gets another one in the sequel, Equestria's Most Wanted. After giving up violence and becoming a pacifist, he is seconds away from achieving full enlightenment... only for Celestia to scream "DADDY!" when she is attacked. Tydal instantly breaks his vow and brutally murders her attacker, then warns an entire asylum that he is going to destroy them if they come near his girls again.
- RealityCheck's Nyxverse: Twilight's Love Interest, Ink Spot, becomes this to Nyx by the time he and Twilight get married. Best exemplified when he fights off Tirek to protect her, and later warns Discord — in all seriousness — that if Tirek's rampage, which is to blame on Discord's actions, have permanently harmed Nyx in any way, he won't need his magic to tie Discord's neck into a knot.
- The Life Of A Wanted Changeling: Bugze may be an unlucky, clumsy, and unskilled changeling, but threaten his daughter Nightshade and he's capable of delivering a Curb-Stomp Battle to anypony from platoons of Royal Guard to Princess Celestia herself
- Escape From the Moon: In the sequel The Mare From the Moon, Discord is very protective of Fluttershy, and makes it very clear to Spliced that he knows of her past with experimental plagues and what will happen if she harms Fluttershy or anypony else in this world with them.
- A Diplomatic Visit: Literally with Swift-Pad - the instant he hears somepony yelling angrily at the young filly he's talking to and sees her eyes widen in fear at their voice, he immediately steps between them to keep the filly safe. Even when said filly is Diamond Tiara and the one yelling is her own mother, it's the way of his people to protect children.
- Orochimaru, of all people, is one in the fic called A Father's Wrath. In this story, he is Naruto's father instead of Minato. On the lighter side, he cares deeply for his son and his actions - including joining Akatsuki and forming the Sound Village - are all to protect him; he has found a source of redemption. But threatening Naruto is the fastest way for him to remind you that he wasn't called The Snake Sannin for nothing. Just ask Hidan.
- Naruto in Win Some, Lose Some, a collection of one-shots. Naruto's warning when Kurenai, Hanabi, Ebisu, and Konohamaru find out about his (adoptive) daughter basically amounts to "If you tell anyone about my daughter, I'll kill you. If anyone tries to harm her, I'll kill them. If anyone kills her, I'll burn Konoha to the ground." Turned Up to Eleven because the Nanabi is sealed within her, meaning the Kyuubi is protecting her too.
- Daiki from Destiny Is A Hazy Thing is this for Naruto. One scene has him tampering with Naruto's seal to allow him, Naruto and the Kyuubi to talk with his real parents. He promptly spends several minutes slowly brutalizing Minato's soul.
Neon Genesis Evangelion
- A Crown of Stars: While Shinji is telling he does not believe he can forgive his abusive father, he is told that in timelines where his mother Yui did not die Gendo is an actually scarily overprotective father.
- The Child of Love:
- HERZ: Shinji hates killing
but threatens his wife or his daughter and he WILL do whatever it takes to protect them.
- Neon Genesis Evangelion: Genocide: Nakajima's father plots against and eventually assassinates Keel Lorenz in order to protect his son.
- The Second Try: Shinji, like his wife Asuka, is very protective of his post-Third-Impact family, though he keeps his cool better than Asuka...most of the time. Anyway hurt her or their daughter Aki... And. You. Will. Die. You'll not even see it coming. The MP-Evas learnt this the hard way.
- Muzzled shows a moment where Zoro literally resorts to biting Marines (after having his swords taken away and his hands tied) who tried to separate him and the kidnapped Usopp and Nami to trap Luffy. Even more awesome than it sounds given his fighting style. His bites break bones.
- "This Bites!" shows this in spades during the SBS broadcast on Omatsuri Island where no few amount of viewers are forced to listen to their friends and families break-down and be devoured by Lily-Carnation. Some of the reactions are as follows.
Captain Dugongs: FIND ME THAT GODS-BE-DAMMED ISLAND... SO I CAN RIP HIS F—-ING B—TERD'S SKULL OUT THE BACK OF HIS HEAD AND CRUSH IT WITH MY OWN BARE FLIPPERS!!!
Whitebeard: I may not be able to sink that island from here...But I am very tempted to try.
Ace: Because this broadcast is the the only thing keeping me from... BURN[ING] THAT F—-ING ISLAND TO ASH... THAT'S IT! HE DIES NOW!
Garp: How dare you do this to my grandson... Buster Call? No... that's to hands-off. We can destroy that island after I've ripped that monster apart WITH MY OWN TWO HANDS!
Dragon: I know you won't lose Luffy...but if you don't kill that monster for this, then I will.
- Luffy doesn't give a flying rat's ass if you are a god, just try to glare at his crew and you can choose your grave's emplacement. Hell, he even stands up to his grandpa because the guy showed hostility towards his friends.
- Silver, from Pokémon: The Great Adventure. The man is mercilessly protective toward Ash in particular and doesn't think twice before jumping at Mewtwo's throat for petrifying him. As the Legendaries say: "It's safer to attack a baby Kangaskhan in his mother's pouch than a kid Silver took under his wings". Did we mention he is a very old Ancient and an Ice Aura Master?
- Meyer, as per canon, is this in Pokémon Reset Bloodlines. When Belmondo kidnapped Clemont right from his bedroom, Meyer confronted him as the Blaziken Mask and broke the guy's arm, warning him not to try something like that ever again.
Rise of the Guardians
- Light of the Snow Red Village is an AU fanfic that answers the question, what if Kenshin and Tomoe had a child? After Tomoe is killed much later in the timeline due to treachery from his superiors, Kenshin takes to wandering with his daughter Hikari. Throughout the story Kenshin is fiercely protective of her well being and happiness, even going so far barring her from learning kenjutsu (he later allows it, after it's pointed out by another character that it's hypocritical of him while he carries a sword himself). Following some adventures they eventually end up in Tokyo at the Kamiya Dojo, where the manga timeline begins. Currently incomplete, but it's a great story nonetheless.
- Siegfried Schnee and Andreas Arc are very protective of their children, Weiss and Jaune respectively. Siegfried went on a Roaring Rampage of Revenge and deposed his father as CEO of the Schnee Dust Company after he caught wind that he abused Weiss, specifically.
- Taiyang Xiao Long and Ysengrim Belladonna, Yang and Blake's fathers, are also this.
- White Sheep (RWBY): When Taiyang finds out that his daughter is being held by Ironwood, he personally comes down to threaten him—despite Ironwood being a respected general in control of the most powerful military in the world. Tai says he will kill Ironwood if Yang comes to any harm. Ironwood points out that if Yang comes to any harm, Jaune has threatened to wipe Atlas off the map, so Ironwood really can't find it in him to care about Tai's threats.
- Sleepwalker is deeply torn by angst and loneliness over his being exiled from his home dimension of the Mindscape and trapped in Rick Sheridan's mind. He doesn't have any doubt at all about one thing, though. If you threaten Rick Sheridan or any of Sleepwalker's other close human friends, you are in for a world of hurt.
- Anyone who hurts or upsets the de-aged Kirk can expect to face Vulcan wrath. This includes crew members. When a visitor hauls Kirk up by his shirt, Spock reacts with cold fury.
Spock was utterly expressionless, eyes devoid of anything but pure ice. That in itself was scary, because [the security team] knew that no one was as pure cool Vulcan as their Vulcan when he was restraining the urge to kill someone.
- Kirk himself becomes more and more protective of his crew as he gets older, culminating in his saving them from the Klingons in one of the final chapters.
- Kirk (empowered by Khan's blood) in That Was A Good Fight. When a shapeshifting alien vampire thing threatened his crew, and specifically, Spock, they had to clean what remained of the creature out of the floor tiles.
- The fic Safe and Sound has a couple of examples:
- Khan is the most prominent. Like in the film, he is this to his crew, and is prepared to kill Dr. Korby in the most painful way possible upon discovering that the man killed all but five members of his crew. He later nearly does carry it out after his surrogate daughter, Lucille, is taken by the man. Said surrogate daughter is able to convince him not to.
- Spock gets a moment towards the end of the story. Korby kidnaps a pregnant Uhura too, and when Spock sees Korby hit her, he attacks him in rage.
Spock: (through a forced mind-meld) You hurt my bondmate. You threatened my child.
- McCoy also has a moment when trying to take back his daughter, Joanna, from his crazy ex-wife. "Once you took everything from me, including her...and hell, I'm not letting you take her again!"
- Kirk to his crew, and Lucille. Note that in this story, he's empowered by augment blood.
- Spock again in the fic Written in the Stars, at least the Prime version. The Prime Fem!Kirk explains that when she was pregnant, she was taken hostage by the people of Gideon (TOS episode "The Mark of Gideon"). Lesson to be learnt: Don't kidnap a Vulcan's pregnant mate. It will not end well.
- In Supernatural's Deterioration of Reason, OC!Gabriel was already shown to be a protective big brother over Castiel and his Berserk Button is if any harm comes to Castiel. But when the demon Belial, who had kidnapped and tortured Castiel, implied that he did something else to Castiel, not only does Gabriel go into Tranquil Fury, but it's revealed that God Himself has had enough.
There was no way for the overwhelming wrath of God to be made evident through mere behavior. The archangel was no longer responding to the demon's mocking himself for the light that surrounded his already blinding form had no place on the conceptualized wavelength of mortal comprehension; it was the response of an incensed Father to the torture and ridicule of one of his sons, it was the vengeful mark of the Lord Himself.
- In Supernatural's Crossing the Line, John Winchester kills a human being for the first time because it was heavily implied said person had molested/sexually assaulted a ten-year-old Sam.
Team Fortress 2
- In the Team Fortress 2 fic Paternal, the RED Spy becomes this to the BLU Scout, protecting him from the Administrator's henchmen at all costs and even facing down the Administrator herself to keep him safe. Discussed by the BLU Engineer in Chapter 26 after Heavy and Pyro express wishes to kill the Administrator's Spy for sexually assaulting Scout:
Engineer: Sorry, boys, but I think Red's earned the right to kill that son-of-a-bitch. I don't know if any of you are fathers, but I know that if someone had hurt my daughter, I'd take him out back and shoot his brains out for even touching her. I'm sure Red wants to do the same thing to Bane for what that snake did to his son.
- Exploited by the Administrator, who knows that the RED Spy has a doomsday device activation code that she gave him many years ago when they were dating and which, in turn, is actually on a pair of dog tags that the RED Spy gave to the BLU Scout when he was little. After BLU Scout shows his father the tags, her plan changes shape: capture Scout and use him as a bargaining tool in exchange for the tags, knowing that the RED Spy will stop at nothing to ensure his son's safety.
Time Fixers: Nicktoons of the Future
- Danny is very protective of his children (for good reason), but when faced with an illusion of his worst fear, he found the will to brush past it when he heard Darry's cries for help. He also nearly blew SpongeTron to pieces when it looked like he blew apart Yuki, until it turned out to be a plant clone and his real daughter had been captured by Undergrowth. Danny also snapped at his friends when Cindy accused Darry of being a threat due to his unstable ghost powers.
- A flashback in "Nicktoon Genesis" shows SpongeBob karate kicking away a giant robot that was about to crush his infant son, and fiercely warns Professor Calamitous to NEVER hurt his children.
- Timmy blows off an important meeting at work to fly into space and rescue Tammy and Tommy from a planet of his clones.
- Optimus Prime and Ratchet in Things We Don't Tell Humans. Optimus is a fan of children, and Elita puts off telling him about how badly Quicksilver was treated because she knows he'll react badly (he does, and it's a little terrifying). Ratchet tries to pick a fight with a general who dismisses Prowl as just a numbers guy.
- Ironhide is implied to be one (and seems to have adopted Sam and Carly). So is Tom Banachek, if the Autobots' dread of telling Tom and Dana about Faust's "capture" is anything to go by.
- Don't mess with Annabelle Lennox. Not only would that tick off her actual father, Will Lennox, but it will also anger the Autobot Weapon Specialist, Ironhide. And probably most of the other Autobots, who are rather fond of her. Barricade learned this the hard way.
- Every single male Autobot that hears Miko's backstory involving being a victim of human trafficking in Dirty Little Secrets. Fowler as well.
- Megatron is very protective of Sheba in Shebakoby's fanfic series Prisoner of Destiny, The Big Capture of 1999-2006, and particularly part 7 of the collaborative Shadow of the Guardian co-written by Conveyus-Prime.
- Two examples occur in Sire and Sparkling - first, Optimus warns Megatron that the tyrant will have to answer to Optimus if he does anything to severely harm their sparkling Valour, then Megatron yells at Starscream when the Seeker insults Valour.