Yuuma and Yuuki

Yuuma's Whimsy : Yuuma wants to bother Yuuki so he totally does. Yuuki rolls with it and grows to develop a "zone" in which nothing bothers him, honed by ignoring Yuuma and his random tendencies. Of course, Yuuma wouldn't be self-indulgent without being even stranger so sometimes Yuuma's random whimsy is to hug Yuuki or something affectionate and it hasn't been once or twice that their teammates have literally (and figuratively) torn their hair out trying to figure out, "You were literally poking him in the cheek two minutes ago. For fun. While Yuuki was practicing. Why are you hugging him now? Do you like him? Hate him?"

Arguments : Yuuma and Yuuki are always logical arguers. No one bothers fighting with them (with words) because it's pointless. There's been (many many many) bets about who would win if the twins fought each other. When it finally happens, there are a lot of theories but no one expects the childish outbursts the twins use that involve but are not exclusive to: height, age, family, diet (aka what they can and cannot eat), and looks (though they're twins). 

Sore Spots : Yuuki gets into fights, sure, but he's generally pretty level-headed. Until someone mentions Yuuma. In which case, bring on World War III because that is essentially the brawl that erupts when said insult happens. Only one person has ever insulted Yuuki in Yuuma's presence. That person no longer exists. 

Pranks : Although Yuuki and Yuuma are pretty mature, they're surprisingly child-like when it comes to some things. One of them is pranks. They're never planned for harm but just for some fun, mischief, and general taking advantage of being twins.

Switching Classes : Enough said. 

Fickle : Everyone knows Yuuma is self-indulgent. So to a new member of the team or class or something, Yuuki has to translate the completely random yet actual reasons why Yuuma is doing all this insane stuff. ("He's upset but not that upset." "He's completely angry." "He's deemed me worthy of his affection." "Oh, that's just to mess with you completely.")

Love Interests : Food for thought. What if these twins fell in love with twins? And Yuuki liked the one closer to Yuuma and Yuuma liked the one closer to Yuuki? And it was like really cute?

The Confession : Being as close to the Sasaki twins as they are, the Kim twins decide to (being just as mischievous as the boys are) switch places. The boys, obviously, recognize the girls but take the opportunity and either pretends not to notice to compliment her (Yuuki on Yejin) or immediately remarks on it, reasoning not that "I know your sister better than that" but "I've been watching you so obviously I'd know" (Yuuma on Soojin).

P.S. : Yuuki sends Yejin a following text. "P.S. You really need to work on your acting" an hour or so after, revealing he'd known the whole time. 

ABC

I Swear : Yuuma does not swear. Yuuki swears like a sailor who hasn't seen land in years. But when Yuuki's with Yuuma, the swearing magically disappears. (Another twin quirk their friends have long gotten used to.) Of course, there tends to be slip-ups here and there. When it's during a match, Yuuma usually lets it go but when it's touching on his last nerves, Yuuma mutters, "Coconut" (his allergy) and Yuuki backs off whatever he's talking about immediately, expression going so far as to change, and pinches his ear while backtracking. (Yuuma has mastered the art of shutting down the argument, raising morale, etc to avoid the awkward gap.)

Else : No one else is allowed to swear in front of Yuuma with Yuuki there. Ensured. 

Code : Yuuma and Yuuki have a lot of codewords. (The one above is just one example of it.) People call it a twin thing, but to be honest no one knows for sure.

Tic Toc : Yuuma and Yuuki have distinctive body language and tics but every so often, they'll randomly switch. Yuuma, for example, might use his hands while talking in a way that Yuuki usually does or Yuuki might say something in a way that people would usually attribute to Yuuma. It drives some people - the ones who tell them apart by their tics - nuts and it's worse because Yuuma and Yuuki have no idea that they're doing it half the time.

Multilingual : Yuuma and Yuuki switch languages when they don't want anyone to understand them or if there's someone they're talking about in the same room. Korean. English. 

Road trip : Driving, Yuuma follows all the rules but mutters insults under his breath about the ones who don't. On the other hand, Yuuki has all the road rage. Yuuma has become temporarily deaf in one ear due to it before. Sometimes, Yuuma debates wearing ear plugs on one side.

Sleep Deprivation : Yuuma gets more random and his whims become completely baseless to the point that there literally is no reason; Yuuki knows Yuuma is sleep-deprived when there is no reason that he can decipher. Yuuki is surprisingly functional the first day but during the second day, his reactions slow, his train of thoughts drop and / or swerve to completely random topics, his filter disappears completely, and his whims become acted upon aka he becomes more like Yuuma on Yuuma's normal days plus some; Yuuma is often called by their friends because yeah, no one can handle two Yuuma's.

Caffeine : Yuuma is more of a tea person while tea and coffee has no effect on Yuuki at all. 

But : Yuuki loves hot cocoa. It doesn't keep him awake but I mean like, can you say no to hot cocoa?

Before College : Just to clarify some points.

Rooms : Yuuki and Yuuma used to have separate rooms. 

College : Because they can't stay in high school forever. 

Majors (And Minors) : Yuuma wants to be a physical therapist so he's majoring in biology and minoring in kinesiology. Meanwhile, Yuuki is double-majoring in neuroscience and biopsychology as a pre-med student.

Chemistry Lab : They take it at the same time because of their majors. 

Experiments : Yuuma decides the experiment is dumb and does some other lab that's more interesting while Yuuki flips out on his twin because seriously, man. 

Roommate Shenanigans : They live together. It's a wild ride. 

Alarms : Yuuki is a heavier sleeper but some days he has to get up earlier than Yuuma. Of course, that means that alarms don't always work. Cue sleeping Yuuki, annoying alarm, and wants-to-sleep-longer Yuuma. When this occurs, Yuuma throws whatever's nearest at Yuuki. It has gotten to the point where Yuuma now has an arsenal. 

Arsenal : Grows from softer to harder and includes a: hackysack, stuffed animal, pillow, small book, larger book

Bed : Yuuki is warm. Yuuma gets cold. During the winter, Yuuma has slipped into Yuuki's bed multiple times. There's a lot of complaints but since when has Yuuki won against Yuuma and his capriciousness? 

Feet : Yuuma sometimes startles Yuuki out of bed with his cold feet. 

With Sooyeon and Yuki (OCs)

Meet-Cute : Sooyeon and Yuki live on the floor above Yuuki and Yuuma. Sooyeon's key stops working when opening the door. Of course it's because it's the wrong door. ("What are you doing? I'm already calling the cops!" in the background)

Names : Sooyeon calling "Yuki" but the pronounciation is the same so Yuuki and Yuki begin arguing over who is the best one and how to differentiate.

Best One : Yuuki and Yuki begin to make it into an inside joke and even compliment each other jokingly. ("I guess you're the better Yuki, but just this time.")

Spot : Yuuma shows Sooyeon his favorite quiet spot. Yuuki complains, turning to Yuki, "He's never shown me that spot." Sooyeon turns around with a dry, "The spot wouldn't be quiet anymore if he did."

Winter : Sooyeon and Yuuma love hugging the Twoki because they're warm but Yuuma is colder than even Sooyeon. Yuuki and Yuki do rock-paper-scissors to figure out who cuddles who to share the warmth. Yuki tends to win and choose Sooyeon but then the Yuutwins won't share warmth because it's "not manly" sometimes so Yuki and Sooyeon work it out so that sometimes Yuki loses on purpose so that both Yuuma and Sooyeon can get warm cuddles. 

Summer : Hugging Yuuma is the best because his skin is so cool. He complains a lot but in the end, he doesn't make them stop hugging him and lets them cool down. 

Studying : Pointing out stuff and making snide comments, making ways for memorization easier. Complaining together during finals. 

Oops : Sooyeon and Yuki falling asleep on the Yuutwins. The boys desperately trying to remain chill and somehow not teasing each other to avoid mutual destruction. 

Trained : Sooyeon is a sprawler who loves sprawling on others. She trains them to turn the page of her books for her when she taps them or something while she's draped across their laps. She falls asleep like that when it gets late. They get used to it.

Got My Back : Yuki and Yuuki lean on each other back to back. When doing science, Yuki tends to get frustrated and stand up quickly, huffing and going on a walk. Yuuki falls backwards since he was leaning on her so heavily. Yuuma always catches it from day one so he never falls. When doing it with Sooyeon, she warns her calmly but after a while, Sooyeon starts to predict it too. 

Kiss : Yuuki and Yuki's is an accident / dare. From before they were a couple.

Tears : Sooyeon walks in crying. Yuki calls Yuuma and Yuuki asking who it was. It becomes a schoolwide hunt. Sooyeon laughs when she hears about it because it was a good movie.

But Really : Yuuki finds the perpetrator first. Tells Yuki because as mad as he and Yuuma would be, Yuki is the most furious.

Cheerleaders : Sooyeon and Yuki cheering the boys on in volleyball games.

Rainy Days : Sooyeon loves the rain but while being warm and inside, not outside and wet (especially not on the way to class or back to the apartment). Insert one of the boys finding her staring at the rain with a pout - literally, a pout - and just throwing his jacket on top of her head, smiling, and basically dragging her to the bus stop / apartment / car. She's still wet by the end but she's smiling and she gives him a quick hug before stepping inside. (Bonus if she has to give him back his jacket, and Yuki spots it hanging and starts teasing her about it.) 

I Won't Get Sick! : Yuki usually has the constitution of a horse. She walks through hospitals and will walk out with not a single virus (but yes to split knuckles - "Just that once Sooyeon!" - when some jerk was picking on a group of little kids). But Yuki seems to get sick only when it rains. She absolutely loves rain and spends hours out in it. When she gets back, Sooyeon tells her to dry off and "Don't you dare fall sick! I'm not going to take care of you if you fall sick because of this!" but Yuki falls sick anyways. (Sooyeon takes care of her anyways.) The twins come in to help take care of Yuki. It isn't smooth, but at least it was fun. 

Bundle Up : Sooyeon dislikes the cold so she layers a lot and just looks like a little kid with all the layers on top of her. Yuki makes fun of her good-naturedly (because think round and fluffy children in the snow) while Sooyeon points out better to look stupid than get sick (reference above). The boys make fun of Sooyeon too. But everyone shuts up about her layers when they come back into the apartment with cold fingers and Sooyeon holds their hands, palms warm and soft even moreso than Yuuki and Yuki because the rain is cold. 

"I'm a gift from God to mankind - or just your life, whichever." : Yuuma is the one who gives outlandish gifts and just overall at choosing them because they're always so random and not necessary, but cool? It's like he picks them out of those airline catalogues or something. But it's so hard to tell him because he's just so desperate for the other person to like it that no one can really tell him to his face that he . Sooyeon is like that but she knows that she and generally gives people the choice of gift card, telling her exactly what you want, or not complaining about what she gives you. Yuki is forever the one who goes over the budget and is always like, "But it was just so perfect!" "But you went over budget!" Yuuki is the normal one who tends towards good gifts, occasionally getting terrible gifts to make Yuuma feel better or gag gifts to make the other person laugh, especially on a bad day. 

Fighting : Yuuki and Yuki get into a really bad argument and refuse to speak to each other. They do the classic thing where they're right next to each other but won't speak. Instead they'll be like "Yuuma, tell Yuki that I don't give a ." "Sooyeon, tell Yuuki that his dumb can go walk off the end of a cliff."

Making Up : Eventually Sooyeon and Yuuma get fed up and lock the two of them in a room until they make up.

Alternative : Sooyeon and Yuuma try to get a plan together to make the two friends again but the school bullies take care of it by targeting one of the two.

Smooth Talking : Yuuki is a smooth talker and drops a lot of smooth lines with girls, particularly Sooyeon who blushes and laughs it off, knowing it isn't serious. (And that was a story and a half because there were a few girls who didn't realize and-) However, he can't with Yuki, which he excuses as not wanting to get hit, but in reality, his brain just blanks. In contrast, Yuuma does it in private, to Sooyeon only, and only on accident. 

Hogwarts AU : Yuki and Yuuki are Gryffindors whereas Yuuma and Sooyeon are Ravenclaws.

Password : Yuki has the amazing ability to always get the Ravenclaw password right even though she isn't a Ravenclaw student. The portrait gets increasingly frustrated and ups the difficulty every time but she still gets it. In contrast, Yuki gives Sooyeon hints about the password (sometimes in riddle form ironically enough) so that technically (though the two have sleepovers and visit each other literally all the time to the point that their roommates know of the other) they aren't breaking the rules. Yuuki and Yuuma give each other the password in code so that no one knows that that's what they're talking about. 

Quidditch : Yuki and Yuuki being chasers and being super in sync but also competing with each other about who can score the most points and such. Sooyeon and Yuuma aren't a part of the team and are banned from Ravenclaw vs. Gryffindor matches because they always cheer for Twoki rather than their own team. 

Soulmate Voice AU : You hear the voice of your soulmate in your head.

Yu(u)ki : Yuki competing and Yuuki critiquing. (Hey, if they're watching the same game, they - I don't know - might be in the same room!)

Friends : Yuuki and Sooyeon are friends. Yuki and Yuuma are friends. (Before discovering their relations.)

First Impressions AU : The first impression your soulmate had of you is written on their wrist. 

Twoki : "Batch." "Butthole."

Yuuyeon : "?" "I really want donuts."