Kenichi: The Mightiest Disciple: Kenichi used to be weak and powerless. He still looks like a little dude due to his training, and even still acts afraid of people many, many ,many, MANY times weaker than him, just because they look scary. This is slightly subverted as the moment the bullies/thugs find out who he is, they usually back off and immediately apologize out of fear.
Played much straighter with Natsu Tanimoto AKA Hermit. He, unlike Kenichi, will NOT hesitate to murder you. He will do so in a way that makes it look like it was someone else, but he WILL beat you black, blue, and red all over.
Bleach: Abarai Renji provokes Ichigo during their training in the Urahara Shop to get him angry. Ichigo, depressed and terrified by his encounter with the Bount, is fighting extremely feebly, and Renji taunts him about his weak fighting to get him to fight with a clear head again. Renji momentarily regrets being so successful.
A Certain Magical Index: Accelerator is the strongest esper in the world, with absurd powers that make him literally untouchable. After he's defeated thanks to Touma's Anti-Magic ability, large gangs start regularly trying to attack him. They're so far beneath his contempt he doesn't even use his active abilities to fight them, yet despite the trail of twisted limbs he leaves behind him, they still attack. They also completely trash his apartment while he's away, but even that fails to get a rise out of him.
In fact, the reason he goes along with the Level 6 project is to make himself so powerful that the very thought of challenging him would be ridiculous. He's been a target of dragon-bulliers all his life, to the point that flashbacks show him (as an 8-year-old child, mind) being assaulted by everything up to a tank division with air support. He knows he's not in any real danger from 99% of the people who try to kill him, but his greatest wish is that all these people would just leave him alone.
Mikoto is often targeted by gangs of delinquents. Even if they don't recognize her personally, she is always wearing the uniform of a school that only includes Level 3 or higher Espers.
Kekkaishi: Gen's backstory is being picked on for being half-ayakashi. They throw mud at him and then act surprised when he throws a boulder.
In the first season of Darker Than Black, humans who know about Contractors have a habit of telling Contractor employees how they think they are nothing but murderous scum who should be wiped out. Luckily for them, most Contractors justdon't care, but this can get ridiculous when Huang is not only verbally abusing someone who can kill him instantly by touching him, but lifting him up by the front of his shirt and screaming in his face.
Happens to Robert Haydn in The Law of Ueki. Taunting a small child who can turn his arm into a six-foot cannon is not a good plan.
Espers in Zettai Karen Children are treated with suspicion at best and as non-human scum at worst. So bad that one of said dragons will grow up to be the "Queen of Disaster" within the span of 10 years. The Children's previous handler, a representative from the education department, used shock collars on the girls in order to control them. She had a Freudian Excuse, though: her own mother was equally sadistic and would lock her up if she wasn't "perfect".
A premise of Tekkaman Blade II, in which the events of Tekkaman Blade led to a segment of humanity gaining the power to become a sort of proto-Tekkaman. These "Primary Bodies" have partial Tekkaman powers, but are inexplicably persecuted, and twice during the series, the Primary Bodies revolt and try to convert themselves into full Tekkamen to take over the world.
In at least "Teknoman" (the English dubbed version of Tekkaman Blade), Ringo's constant attempts to pick fights with Blade in the first half-dozen or so episode could well count as this, seeing as how he's deliberately provoking someone he claims to consider unstable and whom he has seen effortlessly tear through dozens of Spider-Crabs (which are, themselves, killing machines capable of wiping out whole platoons of ordinary soldiers).
This shows up in Fruits Basket. Saki Hanajima (aka "Hana-chan"), one of the main character's friends, is rumored—correctly—to be capable of killing people with her thoughts. The reaction of her peers? "Let's bully her!" Luckily for them, she turns out to be one of The Fettered, but still...
In grade school, she almost killed a boy after he forced her to eat a live newt to support the rumor of her being a witch. It came back to haunt her in middle school.
Code:Breaker: Yuuki, who can manipulate sound waves, tries to use their shared abusive pasts to reason with the poison (and other liquids - she hides her many scars under a thick layer of "makeup")-secreting Lily, to no avail.
In Yu-Gi-Oh! GX Duel Academy is full of people like this (fans call them "Obelisk snobs") who think that Judai is a wimp simply because the red jacket signifies the Osiris Dorm (which he could have been promoted out of as early as the first season if he had wanted to). No many how many Eldritch Abominations he defeats and Shadow Duels he survives throughout the series, the rich upperclassmen never seem to learn. (More than likely, most Obelisk students got there because they had rich parents.)
Manjyome had to deal with a guy like this too shortly after being demoted to Osiris, despite formerly being one of the few competent members of the Obelisk dorm. The guy's name in the dub was "Reginald van Howell III"; a more generic name for a spoiled rich kid there ain't, and his deck was barely better than a Warrior Toolbox.
Cell does this to Gohan in Dragon Ball Z. In an odd variation on the trope, Gohan at the time was hardly a match for Cell. Cell kept pressing his Berserk Buttons so he'd unleash his hidden power and be a Worthy Opponent. Cell underestimated just how worthy he'd be.
Unlike his father who favored the carrot (cake), Babidi preferred to use the stick in controlling Buu. Whenever Buu showed some disobedience, Babidi would threaten to reseal the monster. This continued until Goku scolded Buu for letting such a weak coward order him around and Babidi shortly found himself lacking a head.
Then there's Dr. Gero having repeatedly insulted and berated 17 and 18 who were rebellious teenagers before he forcibly turned them into cyborgs. Cyborgs far stronger than he is, mind you. What happened to him was inevitable.
And there's a double dose of Too Dumb to Live in this example. See, when Dr. Gero built 17 and 18, he realized how difficult they would be to control, and so came up with a new design for future androids that, while still strong, were more limited in their power. Sounds pretty Genre Savvy, right? Except that he then rebuilt his own body, and used the deliberately weakened design on himself rather than the fully powered one that might've enabled him to stand up to 17 and 18 (or better yet, to not even need them in the first place). Yeah, he's a genius, alright.
Naruto: Let's see if we can't isolate and otherwise mentally and emotionally abuse a small child who has a giant fox-demon stuck in him, thus ensuring that he doesn't have a reason to keep said demon there. Let's do this even though, as far as we know, the few people in all of history able to defeat said demon are all long dead.
Goes double for your average smuck who attacks one of the demon hosts. Goes triple for the Kazekage, who has his son Gaara host a demon, and then tries to assassinate Gaara, someone who is for all intents and purposes, invincible. There's making a stupid choice, and there's just plain ought to know better.
In fact, pretty much every village treats their hosts like crap. It's semi-justified in that it's only been a few generations since the Tailed Beasts were first sealed, and so far nearly everyone who is a host for their entire life has lost control, gone insane, or betrayed their village; it's only assumed that they'll ALL be that way. Of course no one points out that those hosts go bad largely because they were mistreated by their villages, and it's not until Naruto goes around knocking sense into his enemies, including the above-mentioned Gaara, that most of the world realizes "Oh, hey, they DON'T have to be despicable monstrosities?"
The Hidden Cloud is the only village at the start of the series that actually treats their hosts well, and that's only after Killer B actually befriended his sealed demon.
There's also Naruto's mother, Kushina. When she first arrived in the Hidden Leaf as a kid, the other kids immediately took to mocking her for her red hair, and she didn't help things when she shot her mouth off about becoming the first female Hokage. Within minutes, she flipped out and beat the living shit out of the bullies. One particular kid actually brought in his older brother to help him get revenge, and Kushina still kicked their asses.
Elfen Lied: When you're pinned down by the monster with the ability to rip you to shreds with their crazy invisible psychic arms, it's probably a good idea NOT to antagonize them. When one character threatens to kill said monster next time he sees her, the monster solves that problem...by gouging out the man's eyes.
Subverted in Slayers with Zelgadis the chimera. Most regular humans either run away in fear or ridicule him for his appearance (and it's also worth noting that he's Nigh Invulnerable and a skilled sorcerer-swordsman), but he doesn't do a thing about it; rather, he either makes a snippy reply or he gets depressed. After he meets the other main characters, though, he begins to take some insults in stride. In the novels, it seemed that he played it straight in the beginning (as "Rezo's berserker"), but it's hinted that Rezo was influencing/manipulating him.
Played straight with most of the Mazoku/Monster race, as well as a few other creatures, such as Beastmen (the fifth novel and the scuffle between Beastman Dilgear and Zelgadis early on say it all).
Played very straight in the first episode of TV series 4. Lina is encountering some pirates, who at this point know that she is Lina Inverse, who has destroyed cities several times (one of them twice). While running away from her in fear, they for some reason decide to taunt her about her breast size, which they know is a Berserk Button. It doesn't end well, although fortunately the scene is meant as comedy, so they suffer Amusing Injuries rather than being killed.
Pretty much the entire plot of Wolf Guy - Wolfen Crest so far if you switch "Dragon" with "Werewolf". To be fair, the people bullying Inugami don't know that he's actually a super powerful werewolf at first. But when the first thing you see a guy do is to make his opponent stab himself with nothing but Deadly Dodging, your first thought should not be to try ganging up on him. When the second thing you see him do is break someone's hand with his face (the guy punching him hurt himself since Inugami is Made of Iron) and you still want to fight him, you've officially become Too Dumb to Live. Later, when Inugami does reveal his true self to Big Bad Haguro Daoh, Daoh becomes crazily obsessed with him (since Inugami caused Daoh, a bonafide emotionless sociopath, to feel a real emotion for the first time in his life: gut-wrenching fear) and deliberately provokes him in the hopes of getting Inugami to acknowledge him as a Worthy Opponent.
Fullmetal Alchemist: During the final battle, Envy just can't resist revealing to Roy Mustang that he was the one who murdered Maes Hughes and then gloating about it. Mustang promptly launches into a Roaring Rampage of Revenge, beating Envy so badly that the homunculus is reduced to begging for mercy.
A small but plot-relevant example from Digimon Tamers: Makuramon shows up during Beelzebumon's fight with Megidramon specifically to stomp on his Berserk Button by mocking him and calling him "pathetic" and "weak". Beelzebumon is a six-foot-tall leather-clad fallen angel who packs two shotguns, gets stronger everytime he kills someone and, coincidentally, needs a little boost in power to beat Megidramon. Makuramon is a monkey.
Impmon (Beelzebumon himself) did this to Devidramon much earlier while he was in a Digital Field. Once he broke out, Impmon wisely fled.
The entire (literal) plot of Sohryuden Legend Of The Dragon Kings, which basically had the bad guys deliberately torment each of the four titular brothers to release their dragon nature, and then inevitably get their asses kicked by them when they did.
Pokémon gives us Ash Ketchum, an unarmed ten(?) year old boy who has never let the fact that a Legendary or armed criminal could reduce him to greasy paste stop him from chewing them out if need be. He even once yelled at Palkia, who just spent half the movie disintegrating space. And the first movie has Ash twice in a row futilely attempt to stop Mewtwo by punching him in the face. (Miraculously, Ash seems able to reason with these titans of the Pokémon world somehow and get them to back off... Most of the time.)
For a mon-to-mon example, try the Advance Generation episode where Ash caught a Torkoal. Prior to being captured, said Torkoal is the target of literal bullying by Steel-types, which a Pokémon like Torkoal would have no problem againstnote for the uninformed, Fire has an advantage against Steel.
Also, some newbie Pokemon on the team get jealous of Pikachu, and try to antagonize him. Never mind that he is higher level than any of them (despite not evolving), and possessed of powerful Shock and Awe abilities. Particularly dumb when Oshawott does it, given that he's a Water type, and thus takes double the hurt from electricity.
Nico Robin of One Piece was bullied by other children when she was young (who, when she retaliated, would go whine to their parents who chastise her. Of course the kids were most likely lying as they picked on her first without provocation. Robin just wanted to be left alone) and abused by her foster parents (well mostly the aunt. Her uncle never did but was too weak willed to stand up for Robin). I repeat, they abused a child who has the power to grow body parts wherever she wants, which, as she proves later when she single-handedly takes down about 50 marines, is quite a dangerous and potentially deadly power.
It's usually Mugging the Monster when it comes to Shanks and Luffy. People rarely appreciate (or even believe) how strong these two are. Two notable examples, however, are Bellamy in the Skypeia arc and Hody Jones after the Time Skip. Bellamy assumed Luffy was a weakling because Luffy wouldn't fight back over a simple insult (he didn't see it as worth the trouble). Then, after Bellamy robbed Luffy's friends, he got Luffy's wanted poster, with a bounty that's almost double his own meager sum. He dismissed it as a fake. When Luffy came back to get what he stole, Bellamy still refused to accept the truth. Cue getting faceplantedwith just one punch to the face.
Hody is an even more egregious example, because not only did he know Luffy had beaten Arlong, but knew his exact reputation right down to recent events and still decided to make an enemy of him. While he arguably could have beaten "Luffy as advertised" instead of "Took a Level in Badass Luffy", Luffy's mere reputation alone should have made him think twice.
A literal and double case of this happens in the Sabaody Archipelago arc with Saint Charloss, one of the World Nobles, a.k.a. the Celestial Dragons, living proof that Aristocrats Are Evil. See, a lot of people would love to show the Nobles the true meaning of pain, but you can't attack a Celestial Dragon, because if you do, they'll call an Admiral and a warship to come attack you. So, Saint Charloss decided to shoot one of Luffy's new friends and enslave him, but he was unaware of two little details when he pulled the trigger: the one he attacked was Luffy's friend, and Luffy does not care about consequences. Attack his friends, and you're on the fast track to death's door, seen here.
Special mention goes to Don Krieg, who picks a fight with Dracule Mihawk, who'd previously turned his several large battleships and army of pirates into one badly trashed battleship with most of his men dead. Then showed up just to finish off Krieg's last battleship due to being bored. Which he did with one swing of his giant sword.
Wow, Spandam! It sure was a great idea to frame CP9, seven of the deadliest assassins in the world, for the Enies Lobby disaster. It's not like they will want to go after your blood when they find out what you did to them! Oh…..
Another, more minor example involving CP9: when Dragon-in-Chief Rob Lucci manages to overwhelm Luffy, Usopp challenges him. To put it in perspective, no antagonist before this had ever managed to beat Luffy when it was a question of who had the better Charles Atlas Superpower, having to use Logia or Paramecia powers if they didn't have some other kind of weapon. Lucci is superhuman, but it's completely related to brute force, and his Devil Fruit power only amplifies that strength by giving him the ability to turn into a leopard. And he managed to beat Luffy, who was lying down in a bloody mess. Usopp, easily the weakest member of the Straw Hats, starts taunting Lucci, culminating in calling him a scaredy-cat. Of course, he was only doing that to provoke Luffy into getting up and finishing the fight. It works.
Tashigi has a terrible habit of picking fights with people that are way out of her league, often ones that have powers that render her own abilities uselessnote Such as Nico Robin and Trafalgar Law, though it's not because she's overconfident or over-estimating her abilities: its mostly due to her Plucky Girl tendencies. It's affected her track record against named characters to the point that it even got her labeled a Faux Action Girl a couple times, even though her main problem is that, even after the Time Skip, she's only at the rank of Marine Captain, and, with only a couple exceptions, the Sorting Algorithm of Evil left them in the dust a long, long time ago (that being at Enies Lobby, where they were using Captains as Mooks).
Arguably the biggest example in terms of representative power levels in the series came in the first chapter, when the 8 million bounty mountain bandit Higuma bullied Shanks, who was formerly a member of Gold Roger's pirate crew, and in canon, is one of the Four Emperors, and easily on par with the Marine Admirals. It may be slightly justified in that Shanks showed no indication of such strength, that it was probably a secret that he was part of Roger's crew, and that reputations like that aren't typically known outside of the Grand Line.
In the Tales of Symphonia OVA, at one point, you see Presealifelessly dragging what used to be a huge tree she chopped down through her village of Ozette as everyone in the village stares at her. All of a sudden, some little kid throws a rock at her and yells "Monster!" Uh, kid? You see that huge tree there? You're a heck of a lot lighter than it is.
It's not like they have any choice in the matter as their bosses WILL kill them if they run away from Kenshiro. Sucks to be a mook in the world of Hokuto no Ken.
Played as Flaw Exploitation in the second episode of Death Note: How do you investigate a murderer who can kill you anywhere, anytime with a magic heart attack? Keep annoying him in the hopes he will try to kill you.
Also Light frequently bosses Ryuk, a God of Death, around. Ryuk puts up with it for a while because he thinks it's hilarious. And even so, Ryuk is only helpful insofar as he finds it hilarious; he outright won't help Light in numerous situations because it would be too easy.
That's not the stupidest thing they can do. See that shy, glasses wearing sickly kid over there? That's Rin's younger twin brother. Hurt him in any manner, and Rin will mop the floor with you. It stands even now. Though, this counts more as Bullying The Dragon's Brother.
Many people in Gamaran ends up doing this to Gama and are defeated. Shown also with Baian Maki: in a flashback he fights alone against ten swordsmen who mock his use of the naginata. Baian hits their leader in the face so hard that it snaps his neck and kills him.
Lots of people screw with half-demons, despite the fact that many half-demons openly possess enough raw power to destroy everyone in the towns that scorn them. True, demons scorn them as well, but even the weakest demon is, generally, much stronger than a human — in other words, they have a decent chance of fighting back. Humans don't.
Shishinki was an absolute idiot to try inflicting an Heroic BSOD on Sesshoumaru. It did not end well for him.
It's commonly interpreted that Nanami in Revolutionary Girl Utena has so much trouble with animals, and at one point actually turns into a cow because she bullied Anthy in episode 3, and as it turns out, Anthy is among other things the proverbial fairytale Witch. An attentive viewer quickly notices that majority of the side-episodes focusing on Nanami's Humiliation Conga show Anthy taking special interest in something related to the episode theme.
In Rebuild of Evangelion, Shinji does this after Asuka is nearly killed. Enraged by Gendo's actions, he begins to attack the headquarters while screaming abuse at his father. Gendo is willing to let Shinji do this until the power runs out... right up until Shinji claims Gendo has never lost anything. Ten seconds later, Shinji is unconscious, without Gendo even moving.
Made worse in the manga, where the incident in question takes place about two and a half chapters before the end of that saga. Somewhat justified; the main characters of Ranma 1/2 are all, basically, idiots.
ROD the TV has Joker treat Paper Master Yomiko's grievances with little respect, ultimately trying to scare her off by showing her exactly what he's done to her love interest. He also does this in the middle of his organization's massive library/headquarters, when her power is the ability to control paper. The outcome, while tragic, is hardly surprising.
Tomoe from Kamisama Kiss is the heroine Nanami's familiar. He's also a Kitsune that is implied to be one of the strongest demons around and who, amongst other things, delivered a No-Holds-Barred Beatdown to a War God. He is both disliked in the demon and divine world and looked down upon for his familiar rank.
It occurs with a few twists in Attack on Titan. Its played straight when the paranoid military police officials openly discuss executing Eren directly in front of him shortly after his powers manifest. Its then somewhat subverted when Levi delivers a No-Holds-Barred Beatdown on Eren, upon which they hilariously realize what could potentially happen if you engage in this trope. However, in a unique fashion, Levi not only lampshades this by pointing out their hypocrisy, but his engaging in this ultimately saves Eren, as it shows Eren can control his power, or that he can at least be incapacitated in the long run if the need arises, which was the best option they could hope for at the time.
Also, Kyouka of Tartaros captured Erza, stripped her naked, and tortured her. Later, Erza broke free and then completely and utterly curbstomped her!
Yu-Gi-Oh! ARC-V: Sora incessantly mocks Shun Kurosaki during their duel, calling his Xyz monsters worthless and even confessing that he's a member of the force that invaded Kurosaki's homeland and turned it into a war zone For the Evulz. Even when Shun keeps countering his moves and dealing massive damage to him, he doesn't let up. Yuya even asked if Sora was out of his mind and asked him to stop provoking him. Sora pays for it when Kurosaki's Raid Raptors - Revolution Falcon carpet bombs the entire battlefield to the ground and makes a building fall on him.
In an early arc of Kyo Kara Maoh, former Evil Chancellor Stoffel von Spitzweig tries to curry favor with the protagonist Yuuri (recently made Maou/Demon King) by kidnapping him. That's actually not the bullying part - Stoffel was only doing it so he could have a chance to talk to the kid alone, and treated him well while he was there. But when Yuuri's retainers naturally objected to this, in the pitched battle that followed Stoffel chose to target the most frail-looking of them: Gunter von Christ, known as not only a powerful magic-user but one of the best sword instructors in the kingdom. It'd be understandable to assume the ridiculously-pretty skinny one was a weakling if it was anyone else, but Stoffel should have known damn well what Gunter could do.