->''"Only those whose lives are brief can imagine that love is eternal. You should embrace that remarkable illusion. It may be the greatest gift your race has ever received."''
-->-- '''Lorien''', ''Series/BabylonFive''

"Had we but world enough and time," the poet said to his reluctant LoveInterest, "this coyness, Lady, were no crime," and he'd be willing to wait for centuries for a RelationshipUpgrade. Normal human beings don't have centuries to work out their romantic lives, but the genres of fantasy and science fiction are full of couples who do. Naturally, if you and your beloved are both immortal, or even just really, really long-lived, you may have all the time in the world in which to fall in love, court each other, hook up, break up, and come back together. You might spend centuries in the WillTheyOrWontThey stage before getting your HappilyEverAfter, and why not? You have all the time in the world for drama. The result is a RomanceArc which could extend backwards into ancient history or forward into the far future.

Vampires may be especially prone to this trope (when they love [[ILoveYouVampireSon other vampires]] rather than humans), but it can also apply to werewolves, TheFairFolk, [[GodCouple gods]], artificial humans or robots, and--in some works--[[WizardsLiveLonger magic users whose power grants them exceptionally long lives]]. A SocietyOfImmortals may display a large number of such relationships, given the greater odds that any immortal character's romantic partner would also be immortal.

Note that any romantic/sexual relationship that lasts for an unnaturally long span of time may count for this trope: it doesn't have to be an entirely happy or healthy relationship. As a result, this trope may overlap with LivingForeverIsAwesome if the relationship is a happy one, but if it is a destructive or angst-ridden one it may fall into [[WhoWantsToLiveForever the other end of the spectrum]]. See YouAreWorthHell for situations where Eternal Love is combined with AndIMustScream.

This trope differs from the MayflyDecemberRomance in that it only applies to couples where both parties are immortal or near-immortal.

Contrast TimeTravelRomance and ReincarnationRomance, where the romance arc is extended through time by other means.
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!!Examples:

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[[folder:Anime And Manga]]
* ''{{Mnemosyne}}'' has a thousand years-long romance between [[spoiler:Rin and Tajimamori]], both immortal and eternally young.
* ''LightNovel/{{Baccano}}'' has two immortal couples. [[spoiler: Firo and Ennis]] aptly demonstrate this trope by [[InnocentCohabitation dating for 50 years]] before finally getting married, while [[spoiler:Isaac and Miria]] have been in constant company for about 75 years. Note that it took the latter 70 years to even ''notice'' they were ageless and immortal.
%%* ''Franchise/SailorMoon'': Usagi and Mamoru's romance.
* In ''Webcomic/AxisPowersHetalia'', it is inferred that [[spoiler: Germany is the Holy Roman Empire,]] meaning that he and Italy found each other again. Daawww...
[[/folder]]

[[folder:Comicbooks]]
* The elves Mesha and Tark in ''Comicbook/GoldDigger.'' Married elves form a psychic bond, which is irrepairably broken if they are ever unfaithful to each other.
* Some relationships for the immortal Comicbook/{{Fables}} work like this, some don't. Literature/BeautyAndTheBeast appear to have this, though they both freely admit that making a marriage last centuries is extremely hard work, and they have their ups and downs. This is contrasted with Prince Charming, who has been married and divorced three times (to Literature/SnowWhite, Literature/SleepingBeauty and Literature/{{Cinderella}}) and by now doesn't even ''try'' to pretend that he'll be ever-faithful to the current object of his affection.
** This trope gets discussed in the ''Peter and Max'' novel, where Max refers to Peter Piper and Bo Peep having "that rare storybook sort of love, where once can't live without the other".
** [[TheBigBadWolf Bigby]] spends a while telling Snow White that he has a combination of this and [[LoveAtFirstSight love at first sniff]] for her, though it took him centuries to act on his feelings, due to his natural reserve and his taking a long time to get sufficiently accustomed to human company and his own newly human body to work out what he was feeling towards Snow. As of issue 50 [[spoiler: TheyDo, and raise seven extremely magical children together]].
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[[folder:Fan Fiction]]
* In the Suikoden III fic [[http://www.fanfiction.net/s/2815865/1/Eternity "Eternity]], it takes a few centuries for Chris and Hugo to get together.
* In the Franchise/HarryPotter fanfic [[http://www.fanfiction.net/s/5402147/1/Death-of-Today Death of Today]]. A surprisingly sane and horcrux free Voldemort and his soul mate Izar Black are set up to become this. But this being Voldemort it involdes playing 'games' and messing up with societal order in an effort to keep themselves entertained for eternity. Still Izar fully expects to become sick of living after a millenia of so.
* In the epilogue to [[http://www.fanfiction.net/s/3406893/1/Infinite-Legacy Infinite Legacy]], Bruce's and Wonder Woman's immortal daughter hooks up with the well over a century old and long widowed Superman. Another author has expanded it into a [[http://www.fanfiction.net/s/8116480/1/Infinite-Memory sequel]], already twice the size of the entire original fic.
* Pops up also in ''Webcomic/AxisPowersHetalia'' fics, given that it's possible to have relationship arcs spanning ''centuries''.
* In the fluffy ''Manga/DeathNote'' CrackFic ''FanFic/ACharmedLife'' Ryuk decides he wants to keep Light forever.
* Subverted at the end of the ''{{Series/Andromeda}}'' fic "[[https://www.fanfiction.net/s/227613/1/Harper-Learns Harper Learns]]". Trance turns out to be a member of some immortal elf race, and intends to sacrifice her immortality to live with Harper. When Harper asks another member of the race why can't they make him immortal as well instead, the guy explains that, for one thing, a sacrifice of her immortality is much more socially acceptable, and for another, he can say from personal experience that this trope doesn't really work out in real life.
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[[folder:Film]]
* In ''Film/{{Hancock}}'', Hancock and Mary have had an off-again-on-again relationship for many centuries. However, this trope is inverted in that [[spoiler: the superman/woman pairs lose their powers when they come together so that they are able to grow old together and die, should WhoWantsToLiveForever kick in]].
* The film version of ''Film/{{Stardust}}'' ended with Tristan becoming a star, and living forever with Yvaine. (In this story, stars are actual, living people, not just mementos of the dead.)
* ''{{Film/Thor}}'': Any Asgardian (or Frost Giant) can have a relationship of this nature with their own species, because of their extremely long life spans. Additionally, as they are going to explore a Sif/Thor/Jane LoveTriangle in the sequel, ''Film/ThorTheDarkWorld'', it's possible that Thor and Sif will end up entering into this sort of relationship later on.
* In ''Film/OnlyLoversLeftAlive'', there's every indication this is the kind of relationship the immortal main pair have. This is in spite of living apart for long periods of time. Their love is compared to [[http://en.wikipedia.org/wiki/Action_at_a_distance#Einstein Einstein's "spooky" action at a distance]], in which particles that become entangled will experience everything that happens to the other, even if they're on opposite ends of the universe.
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[[folder:Literature]]
* In the Literature/MercyThompson book ''Silver Borne'', [[spoiler: Sam and Ariana]] are given a chance to meet again after centuries and rekindle lost romantic possibilities because of their respective long lives.
* Gaston and Freia, from Elizabeth Willey's ''The Well-Favored Man'', are said to have taken decades to fall in love. They can do this because members of their family live for centuries.
* Andrew Marvell's poem [[http://www.luminarium.org/sevenlit/marvell/coy.htm "To His Coy Mistress"]] invokes the possibility of a never-ending love affair only to reject it: since the speaker in the poem and the addressee are both mortal, they'd better hook up sooner rather than risk never getting together at all.
* Literature/TheDresdenFiles has an UnholyMatrimony example between Nicodemus Archleone and Polonius Lartessa, both made immortal through DemonicPossession over a thousand years ago. Many characters, however, reasonably suspect that their twisted relationship cannot be love in the usual sense.
** Particularly when it's shown that Nicodemus regularly cheats on Lartessa. [[{{Squick}} With their daughter.]]
* The Cullen family of ''Literature/{{Twilight}}'' is made up of four vampire couples and a vampire/werewolf couple.
-->"More than eighty years had passed since Carlisle had found Esme, and yet he still looked at her with those incredulous eyes of first love. It would always be that way for them."
--->-- '''Edward, on Carlisle and Esme'''
-->"But of course it made sense that Alice would be watching out for Jasper's future. He was her soul mate, her true other half, though they weren't as flamboyant about their relationship as Rosalie and Emmett were."
--->-- '''Bella Swan explaining Alice and Jasper's relationship'''
-->"I got luckier than I deserved. Emmett is everything I would have asked for if I'd known myself well enough to know what to ask for. He's exactly the kind of person that someone like me needs. And, oddly enough, he needs me, too."
--->-- '''Rosalie's feelings.'''
-->"No measure of time with you will be long enough, but let's start with forever."
--->-- '''Edward to Bella at their wedding.'''
-->"The gravity of the earth no longer tied me to the place where I stood. It was the baby girl in the blonde vampire's arms that held me here now. Renesmee.
--->-- '''Jacob imprinting on Renesmee.'''
* RogerZelazny's ''The Graveyard Heart'' features a couple who achieve their long-lasting relationship through science rather than supernatural forces: they're members of a group that put themselves into cryogenic stasis for years at a time, only coming out of it to throw a huge party, and going back into stasis afterwards.
* In Creator/GregEgan's ''Literature/SchildsLadder'', before Tchicaya finally gets to have sex with his childhood lover Mariama he contemplates "Nothing could have lived up to four thousand years of waiting. Except perhaps an original theorem."
* Creator/DianaWynneJones's ''Literature/ATaleOfTimeCity'' features an immortal or near-immortal couple: Faber John and The Time Lady. They have been separated for thousands of years [[spoiler: but that doesn't seem to have broken their love for each other once they're reunited.]]
* This trope applies to all of Creator/JRRTolkien's Elves, since they are immortal and it is stated that they fall in love early and for life. But an outstanding example is Elu Thingol who meets Maia Melian in a forest and then they spend ''centuries'' just standing there and looking at each other. Also of note are the Valar, who [[TimeAbyss existed before the physical world]] and, as far as we know, entered it already paired up (except for perpetual bachelor and bachelorette Ulmo and NiŽnna, and [[GodOfEvil Melkor]]).
* ''TheSecretsOfTheImmortalNicholasFlamel'' has Nicholas and Perenelle Flamel, naturally.
* In the closing moments of Creator/GregBear's ''The City at The End of Time'', it is revealed that Sangmer and his love, who are forced to spend literally eternity apart in order to prevent the end of everything, meet again every time the current universe reaches it's end, only to part again when the next one is created.
* The High Elves Caelir and Rhianna in Creator/GrahamMcNeill's Ulthuan Duology. [[spoiler: Rhianna must take her ancestor's place on the Isle of the Dead, being trapped there forever, and Caelir, dying from a wound, chooses to stay with her. The two are kept together and will eternally be in a moment of perfect bliss with each other.]]
* Deconstructed by Creator/CSLewis in TheFourLoves. It is pointed out that expecting eros to be more then intermittent is unrealistic and besides unfair to your love interest (your emotions are not his/her fault after all), that you should have friendship and affection as well and in any case, if you really want Eternal Love the only way to get it is to submit it to {{God}} so he can not only love you but bless your love of other humans.
[[/folder]]

[[folder:Live-Action TV]]
* Russell and Talbot of ''Series/TrueBlood'' are a good example. Bill's off-again-on-again love/hate relationship with Lorena ''may'' fit as well.
* From ''Series/{{Highlander}}: The Series'', you've got the four-hundred year old immortal Duncan [=MacLeod=] and his three-hundred-and-fifty year long on-again, off-again snarky romance with the twelve hundred year old immortal Amanda Devereaux.
** There's also a pair of immortal friends of Duncan's who've been married for centuries.
* ''Franchise/{{Buffyverse}}'':
** Spike and Drusilla were together for at least one hundred years before it all fell apart.
** Angel and Darla were together for 150 years.
** One-off vampires Elisabeth and James were together for more than two hundred years.
* ''Series/{{Warehouse 13}}'' provides Bennett Sutton (the Comte de Saint Germain), his wife and his son. Given immortality over five hundred years ago, they don't die (permanently, anyway) and don't age (something their son [[WhoWantsToLiveForever has a few issues with, since he's stuck in the body of a teenager]]). They tend to swing between love and hate depending on the day.
* ''Series/TheVampireDiaries'':
** Katherine wanted this with Stefan. Damon also uses the threat of it against her to convince her to help to delay Klaus' plan until Elena won't become a vampire because of it, by asking her how she feels about competing with Elena for Stefan ''forever''.
** Stefan and Elena's love fits this particular trope. Even though Stefan was a vampire and Elena was a human, their connection was often described as being 'eternal' or 'unbreakable'. Now [[spoiler: that Elena has recently been turned into a vampire, Elena has told Stefan that she wants to be with him forever and spend her immortal life with him for eternity.]]
* The ''Series/{{Supernatural}}'' episode "[[Recap/SupernaturalS07E05ShutUpDrPhil Shut Up, Dr. Phil!]]" features a pair of witches, Don and Maggie Stark, who have been together for 800 years, despite some rocky times.
-->'''Don:''' You're the woman I want to never grow old with.
* The final episode of ''Series/{{Moonlight}}'' has a couple of vampires who have been together for over a century, ever since she saw his boxing match and turned him. Unfortunately, she keeps getting the hots for attractive young athletes, and vampires-human relationships have a tendency to turn... bloody. [[spoiler:She ends up blackmailing the LA vampire community to break her out of police custody, and they retaliate by sentencing her to execution by fire. Despite her infidelity, her husband chooses to join her in death]].
[[/folder]]

[[folder:Mythology and Religion]]
* According to a [[Myth/GreekMythology Greek myth]], the wedding night of Zeus and Hera lasted 300 years, and since they both were happy this was the happiest era in the world's history.
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[[folder:Theater]]
* One wonders if some of Oberon and Titania's relationship woes in ''AMidsummerNightsDream'' stem from the fact that they've been together forever and are getting bored.
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[[folder:Tabletop Games]]
* Warhammer has a few. Orion and Ariel, the Wood Elf King and Queen, are immortal demigod spirits bound eternally to one another, and the vampire counts Vlad and Isabella von Carstein grew to be passionately in love throughout their unlives (until Vlad was finally slain centuries later, and Isabella committed suicide rather than face eternity alone).
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[[folder:Videogames]]
* In ''VideoGame/PlanescapeTorment'', Deionarra is tormented by an eternal love that transcends death itself, aimed squarely at someone [[TheChazz who does not remember having loved her]] [[spoiler:and, as it turns out, never did]].
* One of {{Avernum}} 3's sidequests involve a vampire who asks your party to deal with a group of ogres who have killed his beloved.
* [[LuminousArc3 Anogia]] 's goal [[spoiler:is to live with Miria forever,]] and depend on you [[spoiler: he may die, Miria disappeared from this world or he just gave up and spend his time with Miria the rest of time that he has.]]
* One of the endings for ''[[NeverwinterNights2 Mask of the Betrayer]]'' allows for this: [[spoiler:If you bind Akechi to your soul and serve as a guardian for Kelemvor's City of Judgement, you're effectively granted immortality - albeit with a catch that you can never return to the material plane. Not ready to part with you, your romantic interest (Safiya or Gannayev) will pledge themselves to Kelemvor as well so that they may be with you forever, and the two of you become an eternal BattleCouple.]]
-->'''Gann:''' After all, how many others boast of being able to be together for all eternity? I think the spirits have blessed us.
* PrincessWaltz has one between the BigGood and the BigBad.
* In ''VisualNovel/TheSecondReproduction'' universe, humans and demons can live the same lifespan if they sign a life-bounding contract. Thanks to it, a human can live the same time as a demon.
[[/folder]]

[[folder:Webcomics]]
* Deconstructed in ''ErrantStory'', where the long-lived elves consider a near-eternal relationship to be tragic because you'll eventually grow bored with each other. One of their greatest forms of romance is when your partner dies at the height of your love, so you can go on remembering all the good times without having any bad times to deal with. Thanks to their short life spans, humans were considered ideal for this purpose.
[[/folder]]

[[folder:Western Animation]]
* ''WesternAnimation/{{Gargoyles}}''' Titania leaves Oberon every so often for a couple of decades to have some fun studying humans' magic called "science," hooking up with human men and even having HalfHumanHybrid children (including Fox), although she always comes back when she gets bored. Oberon doesn't mind; he even finds her latest affair with Reynard highly amusing.
-->'''Fox:''' Mother, who is this guy?
-->'''Oberon:''' "Mother"? ''ha-ha'' Titania... what have you been up to?
** Oberon hasn't remained totally monogamous either. He did sire Merlin after all.
[[/folder]]

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