This is a kind of wordplay joke you find characters using, on themselves or others, about how a common expression is very appropriate to the situation at hand... but not for them, since they can no longer use it without it being technically incorrect or highly ironic. Another way to do this is to "fix" the expression so that it works unironically, which changes the expression into a suspiciously off statement for those who have no clue about the character.

For example:

• An undead could say "The city at night is so beautiful it takes my breath away... if I still breathed, anyway."
• Or an atheist might exclaim "Oh your God, what have you done?!"
• Going with a bit of dark humor: "This is an outrage; I won't stand for this! ... And not just because I'm in a wheelchair."
• And to use the trope name: "I would say this is impossible, if it hadn't already happened."

For this humor to work the audience has to know enough about the character to see why the normal statement wouldn't apply. It's not a very difficult task if it can be known just from looking at them or watching them for a bit, but if the relevant bit of background is subtle or requires knowing Backstory the joke can get lost to new viewers. Alternately, a character can be introduced using this kind of humor so the audience and fellow cast can learn something about them, be it that they're somehow different or prone to offbeat humor. If it takes a few episodes for the joke to pay off, it becomes funnier in repeat viewings.

Not to be confused with Could Say It, But.... Compare Insult Backfire and Asymmetric Dilemma. Compare and contrast Forgot He Was a Robot.

Anime and Manga

• Brook in One Piece, who is a skeleton, use any opportunity he finds to deliver one of his "Skull jokes":

• 7-Zark-7 on Battle of the Planets was often given lines referencing his being a robot, such as 'My heart would be in my mouth—if I had a mouth' (perhaps with a line about his non-existent heart added for variety).

Comic Books

• Two examples in Doom Patrol from early November 2009:
  • In the main story, the Black Lantern, Negative Woman says, "I can't for the life of me understand why. Ah, perhaps 'life' was not the best choice of word."
  • In the Metal Men backup strip, Doc Magnus says, "My God (Metaphorically speaking. I don't actually believe in the existence of a supreme being)! What happened here?"

Film

• In the Cut Song "The Jitterbug" from The Wizard of Oz, the Scarecrow says, "I haven't got a brain, but I think I ought to worry."
• In Return to Oz, the flying Gump says as they fall to their Doom™, "If I had a stomach, I know I'd be sick!"
• In Friday the 13th (film), the android Kay-Emm gets her head knocked off by Jason during the climactic battle. After Jason is killed at the end, Kay-Emm's disembodied head is being carried by one of the other surviving heroes, and she states, "I'd clap, if I could."
• A variant in Igor, where Scamper, a reanimated rabbit with an extreme Healing Factor; and Brain, exactly what the name implies; are trying to dismantle a doomsday device. Failing, Brain panics and exclaims, "We're all gonna die! Except you!"
• In the second Matrix movie, Agent Smith describes himself as "A new man, so to speak."
• In A Funny Thing Happened on the Way to the Forum, Zero Mostel's character (a slave) says "This will make my father turn over in his grave". His young master tells him that his father is still alive. Mostel replies "Yeah, but this'll kill him!"
• In Star Trek VI, when the crew of the Enterprise is ordered to go back to a star base to be decommissioned, Spock's reply is "If I were Human, I believe my response would be 'Go to Hell.' If I were Human."
• Emily in Corpse Bride has the "take my breath away" variant.

Literature

• From Halloween Romance: "I defy any human being to fail to learn slow dancing. Then again, I'm technically not a human being anymore."
• In the Dresden Files novel "Ghost Story", Harry, currently a ghost, uses the undead version: "Centuries from now, who knows? Maybe magic will have the side effect of making you really good-looking and popular with the opposite sex - but I'm not holding my breath. I mean, you know. I wouldn't be. If I still had any."
• In the Discworld, Gaspode The Wonder Dog is fond of mutating the expression "pull the other one, it's got bells on" to "pull one of the others, it's got bells on", since being a dog he has four legs. This almost gets him caught when he has to pass for human at one point.
• Mack narrates, in The Automatic Detective: despite his vow to keep his nose clean, "which should have been easy, since I didn't have a nose", he heard something break in the apartment and had to investigate.
• In Simon R. Green's Nightside novels, it's not uncommon for entities without bodies, like animated doors, talking wishing wells, or sentient computers, to bitch about how a confusing situation or Logic Bomb is giving them a headache, in defiance of the fact they don't have heads.

Live Action TV

• A variation of this is found in Doctor Who, with the Fourth Doctor telling a girl "You're a beautiful woman... probably."
• See Asymmetric Dilemma for an example from the Sesame Street comic strip, where a girl says, "If I had a book, I could read... if I could read".
• From the musical episode of Buffy the Vampire Slayer, there's a number that goes, "If my heart could beat, it would break my chest."
  • According to Spike, Andrew is "a breath of fresh air, isn't he? Thank God I don't breathe."
• From 2007's Bionic Woman:

• Dexter does this a lot in voice over, referring to his lack of emotional reactions. Of his adoptive sister, he says "I don't have feelings, but if I could have feelings, I would have them for Deb."
• From Angel

• In one episode of Star Trek the Next Generation, Data visits his birth planet (so to speak), and tells Picard, "I could say 'home, sweet home', sir. If I understood how the word 'sweet' applies."

Music

• The Jonathan Colton song re: Your Brain has Bob—a zombie—use the following line while trying to convince Tom to let them in and eat him.

Radio

• In the original radio version and first book of The Hitchhiker's Guide to the Galaxy, Marvin says, "Well, excuse me for breathing, which I never do anyway so I don't know why I bother to say it. Oh, God, I'm so depressed."
  • There was also his speech for the opening of the new bridge on Sqornshellous Zeta.

Toys

• Bionicle: Makuta Teridax to Carapar:

Video Games

• In Halo: Combat Evolved:

• Kingdom Hearts has Saix, a being without a heart and therefore no emotions.

Web

• On The Other Tropes Wiki, mod Madrugada's forum signature sometimes is, "If I had a piece of chalk, I'd work it out on a wall, if I had a wall." She took it from the third book in P.C.Hodgell's Chronicles of the Kencyrath series, Seeker's Mask. The context is Jame, the heroine trying to sort out how she's related to another character, in a culture that places a great deal of importance on blood relationships.

Webcomics

• Sparkling Generation Valkyrie Yuuki is fighting the Aurochs, a giant bull, ineffectively. She does a power slide beneath him and smacks his meatballs with her hammer.

• Used in this Scary-Go-Round strip.

• There is this exchange between a disembodied character and an animated skeleton in A Modest Destiny:

• Doc Scratch of Homestuck will be keeping an eye, which he doesn't have, on the clock, which he doesn't need.
• In this Blip comic, the first insult which comes to mind for Maggie the talking cat is 'pussy'.
• Evil Inc. had a discussion of "paying through the nose" between Maggie and Red Skull.

Western Animation

• In Archer, "Placebo Effect":

• In House of Mouse:

• Futurama:
  • The robot Bender often uses "Oh your God!" as an exclamation.
  • Another Bender example: "I'm so excited I wish I could wet my pants."
• The Simpsons:
  • Once, a gay character said to Lisa, "If I was a straight 8-year-old boy, I'd be so holding your hand right now."
  • Lindsay Nagael: "This is where the tears would be if I could cry. But I can't. Botched facelift."
• In the Wacky Races episode "Creepy Trip to Lemon Twist", one ghost says to the other, "I'd be bored out of my skull … if I had a skull."
• Superman: The Animated Series: Luthor, discovering who his kidnapper is, exclaims "Brainiac!", to which Brainiac replies "in the flesh, so to speak". Metallo uses the same joke in another episode.
• In Xiaolin Showdown, as :

• A variation in one episode of Adventures in Care-a-Lot: Pleased with a plan, Grizzle kisses UR-2, his robot minion. UR-2 is not pleased, and comments, "I'm sick to my stomach, and I don't even have one."
• Avatar: The Last Airbender: Toph and her friends have never been shy about pointing out her blindness:

• Kim Possible: In the episode where she first meets Felix, Kim is overly conscious of the fact that he's in a wheelchair (albeit an impressively tricked-out one), and keeps being over-helpful. Fortunately, he's amused rather than resentful:

• In the Maryoku Yummy episode "Sound Advice," Baburu, seeing Hadagi pull out an accordion, comments, "It's times like this I wish I had hands to cover my ears."
• From the My Little Pony Friendship Is Magic episode "A Bird in the Hoof", where Twilight Sparkle tries to convince Fluttershy to show a sickly bird some "tough love":

• From the 2010 Pound Puppies episode "Dog On A Wire":

• From the Space Ghost Coast to Coast episode "Chambraigne" has Carl and Little Carl, a pair of giant floating brains, with this exchange: