Ready to launch, currently holding on the ramp as we discuss a possible change of name.
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<br/>[[DoubleArts http://static.tvtropes.org/pmwiki/pub/images/kiri_and_elraine_8108.jpg]]
<br/>[[caption-width:227:If they stop holding hands, she dies.]]
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<br/>->''"I can't live... if living is without you."''
<br/>-->'''[[strike: Mariah Carey]] [[OlderThanTheyThink Harry Nillson]], ''Without You'''''
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<br/>Maybe you've been put through an EmergencyTransformation; maybe a magic spell backfired in an epic fashion; maybe [[MadScientist someone]] decided it would be fun to mess with your life (you know, ForScience!); or maybe it's just the way things work in TheVerse you're currently a denizen of. Any way it went down, you are now literally physically dependant on something (or some''one'') else for your continued existance. You get bonus points if your counterpart is also dependant on you, but this often is not the case.
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<br/>If the link also transmits feelings, pain or injury, this trope overlaps with {{Synchronization}}.
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<br/>For cases where the link isn't vital for either part but simply beneficial, see TheSymbiote.
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<br/>This trope is not about people who can't stand to live apart from each other but are still physically able to do so; for those, head over to either LivingEmotionalCrutch or IfICantHaveYou.
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<br/>!!Examples:
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<br/>[[AC:Anime and Manga]]
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<br/>* [[spoiler:Fai and Kurogane]] in ''TsubasaReservoirChronicle''; the former can't live without the latter, since, [[spoiler:as a vampire, Fai's dependant on blood for feeding, and can only feed on Kurogane.]]
<br/>* Arthur and Shalott in ''AirGear''; Shalott was almost killed when another character kicked through his chest, damaging all his vital organs, so Arthur's organs were transplanted into Shalott. Now Arthur has no organs, so he's dependant on a literal blood connection between him and Shalott for feeding and waste elimination, and will die in a couple hours if the connection is interrupted.
<br/>* In a ''{{Naruto}}'' filler arc, the titular character finds himself deep within one of [[BigBad Orochimaru]]'s hideouts facing ''TheDragon'', Kabuto Yakushi. Kabuto proceeds to use a Secret Technique of the Fuuma clan (Who are mostly loyal to Orochimaru at this point) which connects the hearts of the user, Kabuto and the victim, Naruto through chakra strings. He then proceeds to remove his own still-beating heart from his chest and squeeze it, causing Naruto's heart to take damage as well.
<br/>* Elraine and Kiri of ''DoubleArts'', pictured above, must always be touching (normally holding hands) or Elraine will die of the disease she's infected with but he's immune to and staves off.
<br/>* Charlie in ''{{Vassalord}}'' is a vampire who is dependent on blood from his master Rayflo because, due to his religious views, he refuses to drink from humans as he sees it as a serious sin. (Drinking from Rayflo is also a sin, but in Charlie's eyes is the lesser of two evils.)
<br/>* In ''KatekyoHitmanReborn'', one character can live only because [[spoiler:her organs, the originals of which have been removed, are physical illusions cast by another character]].
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<br/>[[AC:Literature]]
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<br/>* In ''DragonridersOfPern'' the dragons are symbiotes who literally can't face life without their rider: a dragon who fails to find a compatible rider upon hatching will die. If they bond to a rider and the rider dies, the psychological trauma causes the dragon to cross the DespairEventHorizon and suicide. The only exception is a queen dragon whose rider dies while the dragon is waiting for eggs to hatch - she'll hang around until her kids are born and ''then'' suicide, but will be a shell of her former self throughout.
<br/>* In ''[[{{ptitlevz6ksp9w}} Howl's Moving Castle]]'' by Diana Wynne Jones (and TheFilmOfTheBook by HayaoMiyazaki) Calcifer has Howl's heart because Howl ate Calcifer (who is a shooting star) as a child. So, as is often referenced when Calcifer talks to Sophie, "If I die Howl dies too."
<br/>* Inverted in ''HarryPotter'', as the prophecy in the fifth books points out, "Neither can live while the other survives".
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<br/>[[AC:Live Action TV]]
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<br/>* The Jaffa race in the ''{{Stargate}}'' Verse can't live for long without having a Goa'uld larva inside their pouch, until a medicine that has the same effect is discovered in one of the later seasons.
<br/>* ''StargateSG1'': In one story arc, Daniel and Vala put on bracelets that create a link between them, so that to be any more than a few feet away from each other can cause them extreme physical discomfort and eventually death.
<br/>* The same thing happened to Picard and Dr.Crusher on ''StarTrekTheNextGeneration'', except it was an implant. It also made them able to read the other's thoughts.
<br/>* The Trill and their symbionts in the ''StarTrek'' Verse: they share knowledge, and Trills can live just fine without a symbiote, but if a symbiote implanted in a Trill is removed the process invariably proves to be fatal to the host.
<br/>* ''StarTrek'' seems to love this one. The Bynars are a race of cyborgs who always live and work in pairs and can't function alone.
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<br/>[[AC:Comic Books]]
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<br/>* In the MarvelUniverse villainous duo Hammer and Anvil were linked by an alien device that gave them superpowers but also linked their life force.  When one was shot in the head, the other also died.
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<br/>[[AC:Real Life]]
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<br/>* Invoked in a thought experiment often brought up about the abortion debate, where you are asked to be connected to a concert pianist or rocket scientist for nine months because they need your blood supply to live.
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<br/>[[AC:Videogames]]
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<br/>* In ''{{Bioshock}} 2'' it is revealed that if an Alpha Model Big Daddy (the PlayerCharacter in the second game, different from the Big Daddies encountered in the first game) is too far away from his Little Sister, he either dies or lapses into a coma.
<br/>* ''DragonAge'' - Wynne is dependent on a friendly Fade spirit to keep her alive.
<br/>* In the second ''ZoneOfTheEnders'' game, the protagonist Dingo is critically injured and linked to [[GiantRobot Jehuty]] so he can live, at the expense of not being able to survive outside of Jehuty.
<br/>* Similar but opposite to ''Pern'' cycle, the Bond in ''{{Drakan}}'' series connects the dragon and his rider in such way that if the dragon dies, so does the rider, but not vice-versa (justified by the fact that dragons are just that much more powerful). Arokh, for example, has outlived at least one rider already.
<br/>* In the upcoming game ''Enslaved,'' the player character is forcibly bonded to a DistressedDamsel GadgeteerGenius via a RestrainingBolt that will crush his skull if he disobeys her or she dies, because she can't survive in the killbot-infested wasteland on their own.
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<br/>[[AC:Web Comics]]
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<br/>* In ''GirlGenius'', [[spoiler: Gilgamesh ends up supporting both Tarvek and Agatha in this manner when they are infected by Chromatic Immolation]]
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<br/>[[AC:Western Animation]]
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<br/>* After Fry was critically injured in a car crash in ''{{Futurama}}'', his head was attached to Amy's body to make sure he survived until his body was healed.
<br/>* Likewise, in a ''Treehouse Of Horror'' episode of ''TheSimpsons'', Mr.Burns' head was attached to Homer's body.
<br/>*In one episode of ''{{Ben 10}}'', Ben and Kevin are captured and forced into GladiatorGames.  They are shackled together by an energy shackle so that if one dies, the other does too.<br/><br/><strong>reply:</strong><br/>Related to ChainedHeat, I would guess.<br/><br/><strong>reply:</strong><br/>See PuppeteerParasite for the evil version.
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<br/>* Trill in the StarTrekVerse.
<br/>* In TheIncredibleHulk's &quot;Crossroads&quot; arc the Hulk went to a planet where the food is poisonous to animals unless they have a parasite attached. [[http://www.comicbookgalaxy.com/troublewithcomics/2009/10/flashmob-fridays-002-incredible-hulk.html]]<br/><br/><strong>reply:</strong><br/>^Sorry, that should be &quot;a symbiote attached.&quot;<br/><br/><strong>reply:</strong><br/>*In [[{{Bioshock}} Bioshock 2]] it is revealed that if a Big Daddy is too far away from his Little Sister, he either dies or lapses into a coma.<br/><br/><strong>reply:</strong><br/>Often a theme of sappy love songs. &quot;I can't live... if living is without you...&quot;<br/><br/>Another example from ''StargateSG1'': In one story arc, Daniel and Vala put on bracelets that create a link between them, so that to be any more than a few feet away from each other can cause them extreme physical discomfort and eventually death.<br/><br/><strong>reply:</strong><br/>^Same thing happened to Picard &amp; Dr. Crusher on ''StarTrekTheNextGeneration'', except it was an implant.  It also made them able to read the other's thoughts.<br/><br/><strong>reply:</strong><br/>Did a preliminary writeup of the trope, any criticism is welcome. Also, I'm not entirely convinced by the current title (Can't Live Without You), I think it would be better if I changed it to Symbiotic Relationship. What do you guys think?
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<br/>Also, keep the examples coming :)<br/><br/><strong>reply:</strong><br/>Alright, I've noticed that we already have a trope for symbiotes under TheSymbiote (obvious in retrospect, really). So here's what I'm going to do: I'll move all examples of type B (that are simple symbiosis) to TheSymbiote, and keep only the examples of where one character can't live without the other, that was the original purpose of this YKTTW.<br/><br/><strong>reply:</strong><br/>The exploding bracelets of the third Transporter movie.<br/><br/><strong>reply:</strong><br/>Echo JonnyB; we could do with quoting the song &quot;Without You&quot; by [[strike: Mariah Carey]] Harry Nilsen in the page quote.<br/><br/><strong>reply:</strong><br/>* In both the original novel and film adaptation of ''The Rules Of Attraction'' by BretEastonEllis, Sean Bateman's secret admirer kills herself when he seemingly can never take a hint.  In the movie, the suicide scene receives musical accompaniment from the song &quot;Without You&quot; by Harry Nilsen.<br/><br/><strong>reply:</strong><br/>I think the Bynars in Star Trek are similar... they always have to work in pairs and can't function alone. <br/><br/><strong>reply:</strong><br/>*''DragonridersOfPern'' - the dragons are symbiotes who literally can't face life without their rider. If the rider dies, the psychological trauma causes the dragon to cross the DespairEventHorizon and suicide. The only exception is a queen dragon whose rider dies while the dragon is waiting for eggs to hatch - she'll hang around until her kids are born (and ''then'' suicide), but will be a shell of her former self throughout. A dragon who fails to find a compatible rider upon hatching will also die.
<br/>*''DragonAge'' - Wynne is dependent on a friendly Fade spirit to keep her alive.<br/><br/><strong>reply:</strong><br/>Updated with the latest examples. I'm a bit torn regarding ''The Rules Of Attraction'''s example: while it fits the theme of the trope, it's not an exact fit, since the secret admirer wasn't physically dependant on Sean Bateman. On the other hand, though, neither are the dragons in ''Pern'' -- the fact that they can't live without a rider is simply a psychological issue, rather than a physical one; in theory they could survive without a rider.
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<br/>So, uh, what do you guys think? Include both? Exclude both? Include one and not the other?<br/><br/><strong>reply:</strong><br/>I think the Pern dragons were a result of a bio-engineering trip-up, although someone might have to pick up on this for me, since it's a while since I read the prequels. As far as I remember, the fire-lizards the dragons were developed from are ''not'' inclined to suicide if their partner dies, but when they engineered the dragons, they got a nasty shock when a perfectly-healthy queen suicided. I'm sure at least one character mentions &quot;why couldn't someone else have bonded with her&quot;? I ''think'' the idea is that the psychological bond is so intense that it ''becomes'' physical (dragons and riders feel each other's pain, and a dragon without a rider at birth will simply die, which suggests that the rider is a necessity, not a luxury). But then, it's ultimately a mind-link - the only reason I listed it as an example is that ''all'' dragons, no matter their personality or willpower, refuse to outlive their rider for long. <br/><br/><strong>reply:</strong><br/>Alright, thanks for clearing that up. I'll modify the example a bit so it's more clear.
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<br/>Right now I'm leaning on leaving out ''The Rules Of Attraction'', does anyone have any objections?<br/><br/><strong>reply:</strong><br/>In the second ZoneOfTheEnders game, [[GiantRobot Jehuty]] takes over the heart functions of the main character Dingo, or something. Due to this, Dingo cannot survive outside of Jehuty.<br/><br/><strong>reply:</strong><br/>*In the MarvelUniverse villainous duo Hammer and Anvil were linked by an alien device that gave them superpowers but also linked their life force.  When one was shot in the head, the other also died.
<br/>*In one episode of ''{{Ben 10}}'', Ben and Kevin are captured and forced into GladiatorGames.  They are shackled together by an energy shackle so that if one dies, the other does to.<br/><br/><strong>reply:</strong><br/>Fry and Amy in Futurama (tho I forget whose head was attached to whose).  Likewise Mr. Burns' head on Homer's shoulder in the Simpsons (tho that was a Treehouse of Horror ep.).<br/><br/><strong>reply:</strong><br/>In a ''Naruto'' filler arc, the titular character finds himself deep within one of [[BigBad Orochimaru]]'s hideouts facing ''TheDragon'', Kabuto Yakushi. Kabuto proceeds to use a Secret Technique of the Fuuma clan (Who are mostly loyal to Orochimaru at this point) which connects the hearts of the user, Kabuto and the victim, Naruto through chakra strings. He then proceeds to remove his own still-beating heart from his chest and squeeze it, causing Naruto's heart to take damage as well.  <br/><br/><strong>reply:</strong><br/>Added the latest examples, though I'm not sure the ''Naruto'' one fits this trope (looks more like {{Synchronization}} to me). I think we have enough examples for a good article, so I'll wait a bit more and then launch it.<br/><br/><strong>reply:</strong><br/>In GirlGenius, [[spoiler: Gilgamesh ends up supporting both Tarvek and Agatha in this manner when they are infected by Chromatic Immolation]]<br/><br/><strong>reply:</strong><br/>Elraine and Kiri of Double Arts must always be touching (normally holding hands) or Elraine will die of the disease she's infected with but he's immune to and starves off.<br/><br/><strong>reply:</strong><br/>I'm not sure whether this fits in here or in TheSymbiote but I'll list it anyways:<br/><br/>* Charlie in ''{{Vassalord}}'' is dependent on blood from his master Rayflo because in his religious views he feels it's an even greater sin to drink from humans.<br/><br/>The line is a bit blurry here insofar as he could get blood elsewhere, but from his moral standpoint he feels he does have no choice but to depend on Rayflo (which is already a sin as it is) and it is really a physical thing. (Well, mostly...)<br/><br/><strong>reply:</strong><br/>Hmm, my example got eaten up by the engine, it seems. Here it goes again:<br/><br/>* Similar but opposite to ''Pern'' cycle, the Bond in ''{{Drakan}}'' series connects the dragon and his rider in such way that if the dragon dies, so does the rider, but not vice-versa (justified by the fact that dragons are just that much more powerful). Arokh, for example, has outlived at least one rider already.<br/><br/><strong>reply:</strong><br/>In ''KatekyoHitmanReborn'', one character can live only because [[spoiler:her organs, the originals of which have been removed, are physical illusions cast by another character]].<br/><br/><strong>reply:</strong><br/>What an incredibly disturbing image. Can we replace that?<br/><br/><strong>reply:</strong><br/>And call this something else. The term is almost never used literally.<br/><br/><strong>reply:</strong><br/>@ Cidolfas: yeah, sure. Personally I didn't think it was disturbing at all, but I don't really care one way or the other, I'll find another appropriate image.
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<br/>@ [=DragonQuestZ=]: that was the best name I could come up with, and personally I think it fits the trope very well. However, I'm open to suggestions.<br/><br/><strong>reply:</strong><br/>The point isn't just that a name indicates the trope, but that it also doesn't indicate another trope.<br/><br/><strong>reply:</strong><br/>TwoBodiesOneLife?<br/><br/><strong>reply:</strong><br/>OneHeartForTwo, MyHeartBeatsForYou?<br/><br/><strong>reply:</strong><br/>I didn't find the image disturbing either, and it's a shame because that one worked without relying on a caption.<br/><br/><strong>reply:</strong><br/>In Howl's Moving Castle (the movie) Calcifer has Howl's heart because Howl ate Calcifer (who is a shooting star) as a child. So, as is often referenced when Calcifer talks to Sophie- &quot;If I die Howl dies too.&quot; Pretty sure that's in the book, too. <br/><br/><strong>reply:</strong><br/>*Invoked in a thought experiment often brought up about the abortion debate, where you are asked to be connected to a concert pianist or rocket scientist for nine months because they need your blood supply to live.<br/><br/><strong>reply:</strong><br/>I don't know about changing the name, really. Personally I think ''Can't Live Without You'' is exactly what a trope name needs to be: it describes perfectly the purpose of the trope, and is easy to remember. As for the &quot;it indicates another trope&quot; bit, we have [[IThoughtItMeant plenty of other tropes]] that at first glance, judging by the name, aren't about what they seem to be about.<br/><br/><strong>reply:</strong><br/>For some reason the title makes me think of conjoined twins. I think what tripped my memory was the tale of Chang and Eng (Do I have their names right?)<br/><br/><strong>reply:</strong><br/>With the Bioshock 2 example, that only applies to the Alpha model Big Daddies (of which the PC is one). The &quot;production line&quot; big daddies you fought in the main game were not bonded to individual little sisters.<br/><br/><strong>reply:</strong><br/>Inverted in HarryPotter, as the prophecy in the fifth books points out, &quot;Neither can live while the other survives&quot;.<br/><br/><strong>reply:</strong><br/>Just for the record, I'll launch this tomorrow morning (Central Europe Time, i.e. in 10 hours or so) if there are no further objections to the name of the trope.<br/><br/><strong>reply:</strong><br/>In the upcoming game ''Enslaved,'' the player character is forcibly bonded to a DistressedDamsel GadgeteerGenius in this fashion, because she can't survive in the killbot-infested wasteland on their own.<br/><br/><strong>reply:</strong><br/>The song quoted at the beginning, is actually originally by Badfinger.<br/><br/><strong>reply:</strong><br/>End of markup<br/>