#yoonjin au where college roommates yg and sj promised to date each other if they're both single at 30. it's a running joke in their 20s and it's funny and everyone in the group laughs about it until—sj turns 30, and yg realizes he's not sure whose birthday they were counting.

2013 It starts on an ordinary Friday night. Everyone has plans but the two of them and no one else is home, which is normal, except that— “Everyone is out on a date,” Sj notes.

From the couch, Yg scoffs. “Not Jk, though!” “No, even Jk,” Sj corrects him, reading aloud from his phone, “He said he met someone at a café this morning and asked him out ‘cause he doesn’t want to be ‘forever alone’ like us.” He scowls and writes back a strongly-worded reply.

“I hate that,” Yg starts, even though Sj is too busy arguing with Jk to listen, “This entire concept of solitude being a bad thing when it’s not!” Sj’s phone dings. Yg goes on, “People don’t always need to be with anyone—” “Let’s just go out with each other, then!”

He’s obviously riled up by Jk’s messages. Yg sputters. “That’s—uh, well—” He clears his throat one, two times, finding his voice, “—’s not a bad idea…so we don’t, erm…forever alone, whatever Jk said.” Seokjin sounds smug, “Yeah. That’s a good plan. For the future, of course.”

“Of course,” Yg parrots, suddenly feeling his insides go warm and cold at the same time, “When we’re old and single and hopeless.” “If we can’t find anyone else,” Sj agrees, “We’ll be the last two single people on earth but at least we’ll still have each other.” Yg nods.

They’re quiet for a moment as Sj settles on his spot on the couch, beside Yg. “What age do you think that will be?” “Hm?” “When we’re old and hopeless and alone?” “I dunno,” Yg shrugs, putting a movie on, “like 30?”

“Okay, Yg-yah,” Sj smiles, grabbing a plushie and getting comfortable on the couch, “Let’s date if we’re both single at 30.” ***

Roommate promises aren’t supposed to be taken seriously—like how Sj "promises" to game less or Yg "promises" to sleep more. No one takes it against them if they don’t follow through. But their friends found out about THIS promise, laughed, and decided they were in on it.

Like whenever a stranger flirts with Sj at a bar, Jk would pop in completely scandalized, yelling, “How could you do this to Yg-hyung?!” And Hs, trailing right behind him, would tell the stranger, “Our Jin-hyung here is saving himself for Yg-hyung, did he mention that?”

And technically that isn't even what Sj is doing! It wasn't a serious promise! His friends are kidding! But at that point he’s usually too red-faced and flustered to look credible, and the stranger is too turned off to listen to an explanation (and rightly so).

Suddenly, their “arrangement” spreads like gossip on campus and now everyone who’s attracted to Yg is too intimidated by Sj to even approach him. Seriously, if this guy is holding out for /THE/ KSJ—good looks, good humor, good cook—how is anyone else supposed to compete?!

Yg grumbles about it sometimes, after parties or after gigs, the way people strike up a conversation with him only to backtrack when they realize he’s /that/ guy with /that/ roommate. “This is getting predictable,” Sj teases as Yg approaches him, having rejected another fan.

Yg shrugs, unaffected. “Sometimes, I like predictable.” “Is that just code for ‘boring’?” Sj jokes. Yg rolls his eyes, tugging his hyung towards the nearest exist. “It’s code for, there’s no one else I’d rather be home with at 11pm on a Saturday night. Let’s go.” ***

Eventually the years fly by and suddenly December 2022 comes and goes. Seokjin turns 30 and everyone makes a big deal out of it (in a funny way, the way Sj likes) and Yg sits outside the party with his hyung’s gold birthday balloons in his mind. He’s actually 30.

Yg doesn’t know how to transition from “hahaha hyung you’re so old!” to “hahaha hyung so should we date?” He feels silly thinking about it . Was it even that serious? Was it a joke? Yg wonders if his hyung is thinking the same, or if he’s forgotten about it completely.

Sj’s birthday passes along with the window of opportunity to bring it up in a casual, “hey, remember when we were in college and we said a bunch of crazy stuff?” kind of way. If Yg brings it up belatedly, it’s so obviously because he’s been thinking about it for a while.

It’s all in Yg’s head now! KSJ is walking the streets of Seoul at 30, single, extremely dateable, and that’s all Yg can think about.

*** 2023 comes and Yg is counting down the months. Sj complains about not having a New Year’s kiss in January, or a Valentine in February, so Yg decides to bottle up 29 years’ worth of courage and finally do something about it on his birthday.

“What are we doing on March 9th?” Hs asks a few days before, excited to plan a party. “I dunno what you guys are doing but I have an appointment,” Sj announces, ignoring everyone's obvious disappointment. Th pouts. “On Yg-hyung's birthday?” “No party?” Jm mopes too.

“What appointment could possibly be more important?” Nj asks. Sj doesn’t answer. He pretends to act all mysterious about it. (And Yg pretends his stomach didn’t drop at the words.)

Sj gives everyone a hard time about it, refuses to adjust, and so they end up making plans to celebrate on the weekend instead, which Yg doesn't mind. But what he doesn't understand is why someone is knocking at his door at 11:59pm the night before his birthday—

He opens the door to find his hyung there. Cake and wine and flowers and cheesy grin in hand. Yg stares at him, mouth open. The clock hits midnight. "Happy birthday, Yg-yah," Sj says, like nothing is out of the ordinary. "What...what's this?"

“Well, Yoongichi, as of 10 seconds ago, you’re 30. I’m 30. You’re single. I’m single.” He enumerates like it’s the simplest thing, “You know what I’m saying, right?” “I thought you said you had an appointment,” Yg replies dumbly. His brain needs a second to catch up.

“Yeah, an appointment I’ve been planning for 10 years,” Sj speaks slowly. “It was with my college roommate, back in the day…” Yg shakes his head at his hyung’s antics, snapping out of it. “I know. I was there.”

“So, what’s it going to be?” Sj asks, a small smile on the edge of his lips like he already knows it, “Make it fast, Yg-yah, the candle’s melting!” “Same as it was back then,” Yg says, though what he means is it’s been a yes every day since, and he suspects Sj knows it, too.

He blows out the candle and turns 30 with Sj by his side—where he should be, where he always has been this whole time. /end