Insult Friendly Fire

"Mr. Satou: "So you would prefer to live with two cripples instead of with your own family?" Lilly: "If you insist on calling them cripples, then that means you consider me one as well. Is that what you’re saying?”"

- Lilly Epilogue Family Matters

Alice explicitly insults Bob... without realizing that the insult applies equally well to Charlie, whom she most certainly did not mean to insult. Why did she do it? Maybe she didn't think in the heat of the moment, Charlie sneaked in, or Charlie has been hiding the trait that Alice unknowingly insulted. Charlie bears the full brunt of Alice's insult plus the sting of having a friend do so (whether knowingly or not).

Alice may attempt a Verbal Backspace by saying "Present Company Excluded" or "No offence [intended], Charlie."

See also Insult Backfire, Insult Misfire and You Know I'm Black, Right?. Also compare Oblivious Guilt Slinging and Insult to Rocks. Not to be confused with Friendly Fireproof.

If that insult actually hurts, it's Weapons Grade Vocabulary. If Charlie is nonplussed, it's a Milholland Relationship Moment.

Compare Oblivious Mockery, which is more humorous.

Anime and Manga

 * In Naruto, Sakura insults the main character for being an orphan, claiming that his Bratty Half-Pint nature is due to him not having parents to discipline him, not realizing that Sasuke, standing right there, was also an orphan.

Comic Books
"Spider-Man: Mindless Ones? We're fighting hockey fans? Thing: HEY! I like hockey!"
 * One two-part Spider-Man story starts with Spidey dropping by to help The Fantastic Four fight a mob of ugly-looking demons. The Thing clues him in that Doctor Strange knows about the demons, and that they're called the Mindless Ones.

Fan Works

 * It's a Dangerous Business, Going Out Your Door: While complaining to Applejack about how she can't keep up, Rainbow Dash adds that Rarity can't even teleport. Problem is, Twilight's attempts to teach her how caused her accident, and Rarity was already blaming herself for it... so overhearing Dash claiming her inability to teleport makes her The Load doesn't help one bit.
 * In Lilly Epilogue (Good End): Family Matters, Lilly Satou loses her temper with her father over him repeatedly referring to her boyfriend Hisao (who has arrhythmia) and her best friend Hanako (who has scars on almost half of her body) as "cripples", saying that he should consider her one too, as she is blind. He responds by accusing her of puting words in his mouth.

Film

 * In Shrek, Shrek overhears Fiona asking Donkey, "Who could love a hideous beast?". Shrek assumes she's talking about him and is hurt, when, in fact she was talking about, leading him to act angry toward her.

Literature

 * In the Vorkosigan Saga story "Winterfair Gifts", Armsman Roic tells his new friend Taura about an encounter with a swarm of gene-modified bugs, and winds up with a comment about exterminating the grotesque genetically-engineered monsters—having temporarily forgotten that Taura is herself a grotesque genetically-engineered monster.

Live Action TV
"Elle: I say student. You need self-confidence to lecture in front of a classroom full of 30 college kids. Arsonists are socially incompetent. This guy doesn’t go on dates, doesn’t go to parties, doesn’t feel comfortable in front of groups.... Reid: (gives Elle a strange look) Elle: And of course he's a total psychopath. Reid: Of course."
 * In Friends, Ross and Rachel are having a fight in front of everyone. In an effort to attack Ross, Rachel refers to a previously raised issue by saying, "And just so you know, it's not that common, it doesn't happen to every guy and it is a big deal!", at which point Chandler jumps forward and says, "I knew it!"
 * In another episode, Joey attempts to criticize the life choices of his pregnant, unmarried sister while not offending the also pregnant, also unmarried Rachel. Eventually, after going back and forth between the two, he gets frustrated and shouts "One pregnant lady at a time!"
 * In General Hospital, Maxie does everything to put down Winnifred, calling her a geek with no fashion sense and pretty much belittling her in front of Spinelli. Seeing as how Winnie's basically a female version of Spinelli, you can imagine how he takes it.
 * On Criminal Minds, Elle manages to accidentally insult the team's antisocial Boy Genius, Reid, while profiling an Unsub:

"Drew: Hey, Clemens. What has four legs, attracts flies, and shouldn't be in my yard? Greg: *pointing to Drew's friends* Oswald and Lewis."
 * Flipped sideways by The Drew Carey Show: While Drew hangs out in his backyard with friends, his neighbor Greg Clemens walks up with a live horse. Drew is not pleased:

"Grace: How about Sheila if it's a girl? Will: We've been over this, Sheila is the name of a whore. Grace: (to nurse after Will left) He's right, Sheila is a bit whorish. Nurse: We haven't been introduced. Hi, I'm Sheila. Grace: Oh god, I'm so sorry. Nurse: Don't be, I am a whore."
 * Drew can't respond properly at this point, because every insult he thinks of applies to his two best friends. Backfire and Friendly Fire all in one. Poor guy.
 * In Will and Grace, they both step into this one at the doctor's office when they try to have a baby:


 * In the Charmed episode "The Wedding from Hell", when Allison and the Charmed ones confront Jade D'mon at her attempted wedding to Elliot, Allison's boyfriend, Jade greets Allison with "Why, you little witch!", to which Piper says "Hey!".

Video Games
"Shepard: I said a Badass, not some scout whining like a quarian with a tummy-ache. Tali: I'm Standing Right Here!"
 * Shepard in Mass Effect 2, giving a pep-talk to a krogan, while his quarian teammate is present:

"Varric: I swear I will find that son of a bitch (sorry, mother) and I will KILL HIM."
 * Joker manages to do this to himself when talking about quarians; only after he disparages people who live aboard ships their entire lives does he realize he's practically welded to his pilot's seat. (It's real leather!)
 * Dragon Age II, after Bartrand betrays his brother, Varric:

Web Comics
"Mimic: Holy Cannoli! A hideous, disgusting, slimy, nasty, dripping, foul, stinking, oozing, loathsome...[realizes that he has a gelatinous cube in his own party]...er... Rusty: Awkwaaaaaard."
 * In Rusty and Co., Mimic's reaction on seeing a gelatinous cube:

"Ivy: I'll have to stay here over the summer... How am I gonna do that? I can't take three more months of this shit! What if I still can't pass? What if I end up coming back here year after year for the rest of my life? Um... no offense, Frank. Frank: No no, I get it."
 * Schlock Mercenary has this one.
 * Gunnerkrigg Court had the last quip William hurled at Kat applicable to his secret sweetheart. Which resulted in Janet's sharp elbow finding his ribs.
 * Bobwhite. Ivy is talking with her teacher Frank, and she's worried about not having enough credits to graduate:

"Sam: Okay, okay, the guy's a total dork, but I'll leave him alone. He's still a geek, though. Ki:Well, so am I, so don't forget that."
 * In The Order of the Stick, while Elan and Nale are fighting, Elan insults Nale's penis. Then Nale points out that since they are identical twins, Elan just insulted himself. Later in the same fights, he calls Nale a bastard, getting the same reaction. See it here.
 * In General Protection Fault:
 * Ki's father, opposing Nick and Ki getting married, says that he does not approve of a mixed marriage. He is a Japanese man married to a Chinese woman; when Nick points it out, he gets beaten up, and when Ki points it out with her mother in earshot, he quickly loses the argument, and gets Exiled to the Couch even after he apologizes.
 * Comes up in a flashback arc when Ki calls Sam out over his insulting Fooker.

Western Animation
"Amy: But they're mutants. They have to stay in the sewers because they're hideous, ugly, gross monsters...err, present company excluded."
 * In Futurama, when Leela reveals that her parents are visiting;

"Robin: "So he's actually being controlled by aliens?! Eeeewwwwwww!" Superman: "I'm deeply hurt." Robin: "Sorry.""
 * Batman: The Animated Series, episode "Knight Time" - Superman and Robin find out that.

"Patrick: Look at him! He's hideous! That square body, those bulging eyes, those buck teeth, and that stupid tie! Spongebob: *clears throat* Patrick: Oh, but it looks good on you, Spongebob!"
 * Another example can be found in Young Justice, in which one character (Wally aka Kid Flash in this continuity) makes several disparaging remarks about aliens. Cue to Superboy (Kryptonian) and Miss Martian (obviously a Martian) standing there.
 * A weird case in Justice League happened in an early episode when Hawkgirl, Superman, Martian Manhunter and the Flash are traveling through space to see why Green Lantern would surrender so readily to the Manhunters. Hawkgirl says, "You humans are crazy", and then realizes she's talking to Superman, a Kryptonian. Though Superman takes it as a compliment to be lumped in with humanity.
 * SpongeBob SquarePants has Patrick's reaction to Doodlebob in the episode "Frankendoodle":


 * My Little Pony: Friendship Is Magic: After prankster Gilda in "Griffon the Brushoff" gets pranked herself, she belts out a fierce "Reason You Suck" Speech at the presumed perpetrator, Pinkie Pie..
 * In almost every incarnation of Teenage Mutant Ninja Turtles, someone will eventually use the word "Rat" as an insult, with the speaker quickly apologizing to Splinter after he or she does so.