The "Soulmate AU" is a kind of fanfic or fanart that revolves around a setting where everyone has a One True Love, however there is a form of Red String of Fate that ties the soulmates together. Usually these soulmates are romantic, though works with platonic soulmates exist for those who enjoy Heterosexual Life Partners, Romantic Two Girl Friendships, and Platonic Life-Partners.
There are numerous ways for this concept to work. The most common is the "soulmate mark", which is a mark that soulmates share. When the mark appears and what it says varies Depending on the Writer, though the most common interpretation is that people are born with either the first words their soulmate will say to them or their soulmate's name on their body. Another common way for soulmate AUs to work is for people to see in greyscale until they meet their soulmate.
This type of fanwork is most popular on Archive of Our Own and Tumblr. The earliest known cases of the "Your soulmate's name is written on you" prompt date back to the Glee and Sherlock fandoms circa 2011.
The 2009 film Timer might have helped spark this form of fanwork. In it, for a fee a person can get a device that counts down to the point where you meet your soulmate. However, it only works if both soulmates wear a device.
Sub-trope to Alternate Universe Fic.
- Colourblind Soulmate is a Haikyuu!! Fan Vid based on the AU. It uses the "people can't see colours until they see their soulmate" version of the idea. Tooru and Hajime meet when the latter transfers to their school. They become a couple but Tooru starts seeing in monochrome again one day. It turns out Hajime is dying of cancer, and now Tooru won't be able to see in colour for the rest of his life.
- Yuri!!! on Ice:
- all we know is a Yuuri/Viktor Fan Vid is of the "you see in monochrome until you meet your soulmate" variety.
- Unspoken is a Yuuri/Viktor soulmate AU fic. In it, when a soulmate compliments you the words appear on your skin. The problem is, Yuuri is mute in this fanfic.
- Unwritten is a Yuuri/Viktor fic. In it, whatever a person writes on their skin becomes written on their soulmates skin too. Since Viktor is Russian and Yuuri is Japanese, a Language Barrier is involved.
- Osomatsu-san: I'll Carry You Until the End, so Just Hold On for Now is a soulmate mark fic where your soulmate's name appears on your wrist as a teenager. Jyushimatsu meets his unnamed love interest but she doesn't want to tell him her name. He begins calling her "Homura" as a pun on "home run", unaware that she's really his soulmate. Homura doesn't feel she deserves a soulmate, due to her Dark and Troubled Past as a sex worker, and went as far as to Self-Harm her soulmark to the point where it's illegible. Eventually, the two figure out they're soulmates when Homura sees her surname on Jyushimatsu's wrist.
- Tumblr's Dianakko week 2019 featured this prompt on the first day. The most common depiction seemed to be Red String of Fate.
- Soulmark is a fic where this is invoked. Anna goes to the trolls and asks for a soulmark in order to prove that Kristoff is her soulmate. It turns out her sister Elsa is instead.
- but we were in screaming colour is based on the idea that a person starts to see in colour the moment they meet their soulmate; Elsa started to see in colour the moment Anna was born, but she was so young that they never remembered this as they were growing up, speculating that they just ran into their soulmates when some other royals visited Arendelle while they were young (Hans is also told by his brothers that the reason he could always see in colour is because he never had a soulmate). Eventually, Elsa and Anna decide to go to Ahtohallan to try and learn the identities of their soulmates, witnessing the memory of their first meeting in the ice.
- Love Worth Waiting For is a Crossover Couple fanfic involving Mulan. In it, everyone is born with a soulmark of their soulmate's name on their hand. For her entire life, Elsa thought her mark was gibberish, however it turns out to be Chinese calligraphy. Her soulmate is Mulan.
- rise like the break of dawn is Brave crossover one-shot that ships Elsa with Merida. It uses the "your soulmark is of the first words your soulmate says to you" variant.
- You'll Find Your Wings is a Barbie in the Princess and the Pauper oneshot where Princess Anneliese is being forced into an Arranged Marriage unless she can find her soulmate in a week. She meets a woman named Erika who turns out to have a matching wrist soulmark.
- We Meet In Dreams is a soulmate AU Fanvid for the Marvel Cinematic Universe. It pairs Tony and Steve up using the "everyone has a clock that counts down until they meet their soulmate" variant.
- Resigned To Fate (Fading Away) is an It Chapter 2 soulmate fic for the Richie/Eddie pairing where being next to your soulmate heals injuries.
- The Barely Lethal fic "Watering Plastic Plants in the Hope That They'll Grow" is a 'Soulmark' fic based on the premise that the name of a person's soulmate appears on their wrist when they become 13, which simultaneously deconstructs and supports the soulmark idea. Like all Prescott girls, 83's soulmark was burnt off before she could see it to ensure that they would have no attachments outside of the organisation, and Liz has developed a cynical view of the very idea of soulmarks as her parents divorced despite being soulmates as it was apparently "too much pressure" to know their destined partner, to say nothing of Liz never understanding the meaning of her soulmark as it just states '83'. After Liz has worn bracelets or long sleeves to hide her soulmark ever since before Megan started living with the Larsons, she only learns Megan's 'real name' after Victoria Knox refers to Megan as '83' and explains the concept of Prescott's naming system, and still conceals the soulmark from Megan until she's sure of Megan's own feelings for her in turn, Liz wanting to know that Megan loved her and not just because the soulmark said so.
- Deconstructed in Just Close Your Eyes and It Doesn't Exist by Wix, Tony Stark rejects Steve Roger's advances despite sharing a soul mark. This is due to their initial rocky meeting, their less than stellar relationship afterwards, the events of Captain America: Civil War, and the fact that Tony is in a loving relationship with Stephen Strange. This isn't helped by the fact that Rogers only started to act affectionate after finding out that they share the same mark when he and Team Cap came back from Wakanda.
- It was also deconstructed with, news reporter and Tony's friend, Christine Everhart whose soulmate was a corrupt politician which she then later exposed.
- "Look Again" explores Wanda Maximoff's grief as she grew up without a soulmark until the Vision is activated and their names appear on each other's wrists. The fic also briefly looks at the other Avengers' soulmarks, such as Banner and the Hulk supposedly having different marks and Thor having several due to his long lifespan.
- In The Hobbit fic Soulmates And Where to Find Them, each race has different types of soulmate marks: dwarves get their marks on their backs when they come of age, hobbits get theirs on their wrists but only after they and their soulmate have fallen in love, and elves get theirs on their chest when they first see their soulmate. This leads to complications when Interspecies Romances occur as the soulmates get the mark type of their partner's species; as a result, Kili and Thorin both believe they don't have soulmates until Kili gets one on his chest after seeing Tauriel and Thorin gets one on his wrist after courting Bilbo.
- hello goodbye ('twas nice to know you) is a Harry Potter fanfic where Draco and Harry are soulmates. Draco notices one day that his soulmark, which changes depending on the soulmate's thoughts, seems like they belong to Harry.
- J'ai fort lu Platon, mais rien ne m'en reste is a Les Misérables soulmark AU, using the "soulmate's first words" variation, that mostly consists of Enjolras and his amis discussing the implications of the concept (like the fact that a soulmark is completely useless to the many people in 19th-century France who were never taught to read). It deconstructs the common "ugh, I hate this person I've just met but apparently they're my soulmate" plot by specifying that if two people haven't grown into each other's soulmates yet when they first meet, their soulmarks won't record their actual first words to each other but instead the first thing they say, however much later, when they have grown into soulmates. This also sets up the fic's big dramatic irony: that Enjolras has given up on finding his soulmate because his mark is the unhelpfully non-unique "Vive la Republique!", while Grantaire has given up on finding his soulmate because his mark says nothing at all.note
- An Ever-Fixed Mark is a Pride and Prejudice soulmark AU, using the "soulmate's name" variation. It's a deconstruction, critiquing the idea of One True Love that comes bundled with the soulmark concept. In the fic, each person gets only one part of their soulmate's name, making the whole business much less certain. Elizabeth Bennet's mark says "Fitzwilliam", which tips her over into starting a romance with Colonel Fitzwilliam instead of remaining single long enough to get on first-name terms with Mr. Darcy.
- In the Good Omens fic Anam Cara, soulmates don't get marks or any obvious identifiers but Chamuel, the angel of relationships, knows which humans are destined to be together and begins snubbing Aziraphale after his and Crowley's names appear on the soulmate list despite angels and demons not being supposed to have soulmates. Aziraphale is dismayed by this and tells Crowley that the notion of them being soulmates is ludicrous and should be prevented at all costs, only to realize after Crowley gets upset and begins avoiding him that it's too late to prevent them from becoming soulmates because they already are and he was just terrified of admitting it.
- Supergirl (2015):
- Not Alone Anymore is ship fic between Cat and Kara. Cat spent almost forty years of her life without a soulmark until one day it appeared. When Kara arrived on Earth, she received her soulmark.
- Signs is a Kara/Lena and Alex/Maggie soulmate fic. It uses an interpretation where everyone has a compass pointing towards their soulmate. Kara, being an alien, doesn't have one.
- Hey, are you Lena Luthor? is a Lena/Kara ship fic. The first thing your soulmate ever says to you is written on your skin. Lena is infuriated at her completely mundane soul mark, and she hears the phrase an average of once per day. On the other hand, Kara has the oddly rude soul mark "Hey, go fuck yourself!" Written in English, no less, which confused her to no end when she was a young girl on Krypton.
- Your Mark on my Skin is a Stiles/Derek Teen Wolf fanfic. People have marks on their body that represent their soulmate. Stiles has known Derek is his soulmate since sixth grade but Derek took a lot longer to figure it out.
- Pain is an Oliver/Laurel fic where soulmates have Synchronization. Deconstructed in that turns out feeling someone's pain sucks. Sara has a Jerkass Realization upon learning Oliver didn't feel her pain (and thus she slept with her sister's boyfriend for nothing), and Oliver has one when he realizes the near constant sense of heartache and betrayal might be coming from Laurel, making him realize just how badly he hurt her. Laurel meanwhile is forced to drop out of law school, and can't even hold a regular job, as she keeps feeling his pain of combat, torture, etc (although this inspires her to become Black Canary even before Oliver returns to Starling City to deal with her frustration about her pain-induced feelings).
- A more unusual case can be found in Granted, a particularly depressing Oliver/Laurel fic where a person loses their ability to see color after their soulmate tells them they love them for the last time. The fic starts with Laurel losing her color during the somewhat infamous "hallway scene" (set in Season 2). She then has to live with knowing the man she loves will never say he loves her again, and struggles to adapt to living a colorless life. It ends with Oliver losing color when she diesnote , leaving him mourning her death, how much he took her for granted, and the knowledge that now he really will be alone for the rest of his life.
- In NUMB3RS story Love Hurts, soulmates are found when one or both are seriously hurt in accidents and it is mentioned some have died when meeting their soulmate.
- Person of Interest features this with Shaw and Root, as a collection of different versions of their relationship. In Every Story
- In the fic With Your Crooked Heart, most people (except those supposedly incapable of love) have words on their forearm which appear as if by magic at some point in their lives, usually during childhood. The words are in the handwriting of your True Love and may be a name, address, or cryptic clue like a poem or obscure reference. When the clue is obvious, like an address, you can hurry fate along by turning up on their doorstep, but if it's as vague as a line of poetry, you may have to get to know your True Love before the clue begins to make sense.
- In the TiMER-inspired fic Blue Veins, everyone has a magical configuration of veins near the surface on the inside of the wrist that count down to the moment you meet your True Love.
- In the fic Put a Smile in Your Name, everyone is born with the first name of their True Love in their True Loves handwriting on their palm. Databases of this information exist and, for a fee, matchmaking companies will check for any matches between your name and the name on your palm.
- In the fic Finding John, everyone is born with the first name of their True Love like a tattoo on the inside of one finger. With only a limited number of first names, its usually not enough information (unless youre The British Government) to lead you to a person but once you meet your True Love, theyll have your name too and the particular color and shade of your names will match.
- This trope is defied in the fic, To the Limits of Your Choice when Sherlock chooses not to care, or perhaps not to accept the consequences of acknowledging the person symbolized by the soulmate mark on his wrist. When John finds his soulmate, Sherlock asks John to choose between camaraderie with him and romance with her and John also defies this trope, choosing to continue adventuring with Sherlock.
- Cherish Me is a short A Way Out AU fanfic, centered around the headcanon that Leo and Vincent are soulmates who have Touch Telepathy with each other, which gives a plausible explanation as to why they were able to work so well together. It also explains why, in the final battle, Leo and Vincent experience each other's memories every time they attack each other. The difference is that both Leo and Vincent realize they are soulmates, and end up surviving in the end.
- A Deconstructive Parody in the Avatar: The Last Airbender fic "Now Kiss," for the rarepair Sokka/Mai.
- The Legend of Korra:
- The fic Rumble mixes the soulmate AU with the equalist Asami AU. Asami is an Equalist spy on a mission to befriend the Avatar. However it turns out Korra is her soulmate. The fic uses a variation of the AU where soulmates feel each others pain.
- They say that true love hurts. Well, this could almost kill me is a Korrasami fanfic where soulmates feel each other's emotional and physical pain.
- RayDrawlings on Tumblr has a series of "soulmate mark AU" fanarts based on Miraculous Ladybug. Marinette was not born with a soulmate mark like most, which made her believe she didn't have a soulmate. When she meets Chat Noir she gets her mark, but it's a picture of a black cat instead of a name. Adrien subsequently gets a ladybug on his back.
- The short film The String is an original work based on this type of work. It's about a girl who doesn't have a Red String of Fate like everyone else. She eventually finds her soulmate who turns out to be a woman.
- Pn F Soulmates is a take on the powers variant, set in one where various powers are gained once you meet your soulmate, such as being unable to drown.
- Steven Universe: I Can't Believe Dumbledore Died is an Amethyst/Peridot fic of the "the first words you say to your soulmate are written on your arm" variety. Peridot unfortunately has "Man, I can't believe Dumbledore died." on her arm, spoiling her to the twist and leading to several uncomfortable Summers in long sleeves due to not wanting to spoil anyone else.
- Kim Possible: In the Dead Fic Not Impossible, the name of your soulmate appears on your arm once you turn eighteen. Kim's soulmate is shockingly not her boyfriend Ron, but a woman named "Sheyenne Gomez". Kim doesn't realize that her soulmate is Shego. The trope is also deconstructed by Felix when he mentions he had a perfect relationship with his exe Zita, but they broke up simply because Zita had another person's name on her wrist. Felix doesn't believe that two people being soulmates means they're a perfect match. It's also shown that Kim's parents weren't soulmates, but fell in love anyway and are Happily Married.
- Voltron: Legendary Defender: In I'll be your knight (in shining armor), Lance has the unique ability to see the Red String of Fate and learns that Lotor is Allura's soulmate...or so he thinks. Mutual pining ensues between the Galran prince and the sharpshooter.