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Kaeya hums quietly to himself in the corner of the tavern. His leg bounces anxiously under the table as he reads through his assignments for the week, courtesy of Jean. He knew she had much more to deal with than he did, but he couldn't help but groan to himself about how incompetent the people of Mondstadt are.
The assignment at the top of his stack was about going out to Springvale to pick up an order of Philanemo mushrooms. He set it aside and combed through the rest, glass of red wine sitting next to his hefty stack. He's already worked himself through a glass in the last half hour that he's been here.
It certainly didn't help that his anxious tics involved doing something, anything really, within reach. Everytime he took a sip and set the glass back down, it'd be about two minutes before he took a swig from it again.
Diluc is stationed at the counter right now, having recently switched his shift out with Charles. Kaeya has the other's schedule almost memorised, extremely familiar with the work shifts of the place where he spends so much time.
He huffs and shoves his stack of papers away in an angry fit, rejecting the third assignment about a missing pet. The people of Mondstadt were spoiled rotten with incompetence— would it kill them to spend their time doing something other than partying or drinking?
"Kaeya, are you alright?" Rosaria asks as she slides into the seat across from him.
"Yeah, just– there are so many assignments and missions to completely. So many of them are so pointless. I'm a Knight, meant to kill threats, and I'm being sent around town to deliver letters and crates of milk while looking for lost cats." He huffs and stacks the papers up, setting them to the side and lifting his glass of wine to his mouth again.
"Seems wonderful. Sucrose told me it was likely you'd be here. I just wanted to check in and see if you would be alright for the evening."
"Oh, totally. Why wouldn't I be?"
"It's supposed to storm, sometime after midnight. I don't think you'll be here late enough, but if you're not asleep by then I know you get nervous."
"I'll be fine. It's just a bit of rain."
"If you say so. Make sure you monitor how much you're drinking, while you're at it. Don't get carried away." With that, Rosaria stands and leaves the tavern, heels clacking loudly against the polished wooden floors.
Kaeya glances at the clock, reading it to just have turned to ten pm. The tavern doesn't close until midnight, so he assumes he'll be fine to avoid the storm. He turns back to his reports, sorting them into a list that he'll complete them in. He barely notices the time pass and the exchange of his empty wine glass for another. And another. And another, and then another.
"Kaeya," Diluc speaks. His voice is cold and monotone, just like always. Kaeya turns his head up, looking wearily at his ex-brother.
"What is it?"
"The tavern is closing half an hour early, due to the severe storm rolling this way." As if to prove his point, the sky cracks loudly with thunder. The noise makes Kaeya jump, and he quickly realizes why Rosaria stopped in. She was checking to see if he would regress later, in an attempt to warn him for the storm.
Normally, he'd have a better grip on his words and his actions. But the wine has loosened his ability to act serious, and the idea of cowering under a heavy blanket while the storm rolls around them is extremely tempting.
"Oh. I hadn't realized."
"You can get yourself to your quarters, correct?" Despite the fact he knows very well he won't get there on his own, he nods slowly.
"Can you call Rosaria?"
"I can't. The telephone lines are down." Kaeya's eyes widen just a bit at the news of that, and his brain kicks into a heavy panic. His grip on his mentality slips a bit, sliding out of the reach of his hands like water.
"Kaeya? Hello? Are you going to leave, or no?"
"I– I don'... I– can't go outside," He mumbles, fighting every bone in his body to not pull his knees go his chest. His papers are still a mess all over the table, and the chances of spilling the last half of his glass of wine onto the table are more than likely, if he curls up.
"What?" Diluc looks down at him, only because he's taller, but for some reason it still sends him through a panicked frenzy.
"I can just... I don't know," He mumbles. There's embarrassment hot on his face, which wouldn't have been noticed by Diluc if Diluc hadn't known all of Kaeya's giveaways.
"Do you want me to walk you back? You need to get home safe, I don't care about the rest." Diluc crosses his arms, eyes trained on Kaeya.
"Scared," He whispers. Diluc waits for a minute before doing anything, but then he sits down in the chair across from Kaeya.
"Are you alright?" Kaeya nods slowly. He slowly inches the wine glass towards Diluc's side of the table, but only gets about 3 inches closer before Diluc takes it.
"Don' wan'a be alone."
"Well, if we can't call Rosaria or Albedo, I don't know what to do about that. Do you want to stay with me at the manor?" Kaeya nods, watching Diluc rise from his seat with a sigh. "Stack your papers up again while I put this away, and then we can go."
Kaeya's brain is too far gone to care about the organization of his papers. They're thrown together into a messy pile, the exact opposite of his normal mannerisms. Diluc notices it when they finally leave the tavern, lights off and door locked, but he doesn't point it out. He just asks to carry the papers instead, and Kaeya complies.
"Scary," Kaeya whines when thunder crashes above their heads. The sound echos in the air, and Kaeya crashes into Diluc out of fear when lightning lights the skies up for just a second.
"You're not normally scared of storms," Diluc starts before helping Kaeya into the carriage and getting in next to him. "Is there something affecting you?" Kaeya shakes his head stubbornly, trying to grasp his mental state in a firm hand.
Yet, it slides through his fingers like melted butter.
"I'm scared," Kaeya mumbles to himself, finally caving and pulling his knees to his chest. His pants are extremely restraining and it hurts slightly to keep his legs tucked close to his chest, but hes desperate for any type of comfort he can get.
"Why?"
"I'm little, 'luc," He whispers. The raging storm outside almost drowns his voice out. Diluc hears it, though, and in the long-run, that's what matters.
"You're little? What does that mean?"
"Kid." He curls further in on himself, Diluc studying his movements.
"You're a little kid? Are you alright— did something happen at Albedo's? Was it the wine? You aren't making sense, Kaeya."
"I feel like a little kid. It's for— stress, or whatever." Karya mumbles in embarrassment. Diluc goes quiet for a moment, leaving the two in an awkward moment. It ends when Kaeya squeaks and jumps towards Diluc, scared by the sudden crash of thunder.
"Alright. Do you want me to... watch over you? Is that how it works?"
"Mhm." Diluc wraps an arm around Kaeya, tugging him closer so that he's grounded by contact with Diluc. Kaeya is quick to let Diluc take over, holding him close and trying to comfort him.
Neither of them say anything for the rest of the short ride back to the manor. Kaeya doesn't do much, either. Diluc can't tell if it's normal behavior for his current mentality, or if he's being shy— Kaeya was often a mix of everything when he was a little kid, so there's no definite frame to go off of.
Diluc offers to carry Kaeya when they get out of the carriage, insisting that Kaeya will dirty his feet. That, and he's still jumping every time the thunder claps in the sky with great hands, shattering water droplets to fall down onto the Teyvat's surface, quickly creating a mess of every path in Mondstadt.
Yet Kaeya insists he doesn't need help, regardless of the way that Diluc is watching him struggle to get through the mud and make his feet listen to him.
They make it to the front door of the winery's manor and Diluc has yet to see any of Kaeya's childish behavior, with the exception of his refusal to accept help.
"Kaeya, is this how you... normally act? When you're younger?" Diluc speaks when he sees Kaeya lean down to unzip his boots, clearly struggling with fine motor skills but still trying to act like an adult.
"I mean—" Kaeya begins. Diluc cuts him off by telling him to lean against the couch behind him so Diluc can help take his shoes off.
"You can act childish around me. I don't mind it, if anything, I would like to help. I'm very capable of watching children, if that's what you're worried about."
"Embarrassed," Kaeya mumbles back at him once Diluc tucks his muddy boots into the closet.
"There's nothing to be embarrassed about. Is there anything you need to help you feel more... little?"
"Blankie," He murmurs, making grabby hands at Diluc. The redhead doesn't hesitate in scooping his younger brother up, sitting him against his hip while they walk. Kaeya leans into Diluc, hands gripping onto Diluc's shirt to steady himself.
"Any blankie? Or do you have a special one?"
"Soft," He mumbles into Diluc's shirt. Diluc nods, pressing against a bookcase and beginning to walk down the staircase it reveals. Kaeya gasps in awe, eyes lighting up with childish curiosity. Diluc almost forgot that Kaeya hadn't discovered it yet.
"There's a secret base down here," Diluc explains. "You'll be super safe from the scary storm, and no one else can accidentally find you. Is that okay, little blue?" Kaeya nods, yawning lazily when Diluc sets him down on the floor against the couch. Like a real baby, Kaeya notes through muddled thoughts. He huffs in annoyance when he realizes that's the age that Diluc is trying to treat him as.
He's a big kid, not a little baby. Rosaria says he's a big boy all the time, and whenever he gets stuck with Jean she says the same. He's a brave little Knight, not some dumb baby.
He shoves Diluc's hands away when he comes back, a bottle filled with juice in hand. Despite his want for the apple juice, Kaeya would rather not have any at all than drink it out of a baby bottle.
"Kaeya? What's wrong? Did something happen?" Panic seeps into his voice, almost making Kaeya feel guilty for his actions.
"Not a baby," He argues, shoving Diluc's hand away again.
"You sure you're not? You seem to be one to me. You're super tiny, like one," Diluc insists. Kaeya whines at his points, shaking his head and balling his hands into fists.
"'M a big boy!!" He argues, huffing. Diluc offers the bottle again.
"You know, big boys don't throw tantrums like this. It's not a bad thing to be a baby, Kae. If anything, it's even better, hm? You don't have to make any decisions at all, and you get everything you want."
"Everyt'ing?"
"Almost everything," Diluc corrects. It makes Kaeya giggle, mentality slipping even further. Diluc grabs a few of the blankets off the couch and lies them down on the floor, cushioning the carpet even further.
"Otay," Kaeya responds. He caves and finally takes the bottle of apple juice, giggling to himself while he suckles on the bottle. Diluc adjusts them to be sitting on top of the more comfortable blankets, before beginning to try and strip Kaeya of all the excessive accessories he adorns himself in.
Kaeya seems to relax further once he's not bombarded with a ton of trinkets and jewelery, but Diluc knows he'll freak out if he can't find them easily. So he places all of his items up on the counter, out of reach so they won't be in the way but close enough that Kaeya won't worry.
"Luc," Kaeya whines, making grabby hands towards his brother. Diluc is quick to turn around and scoop him up, leaning down to grab his discarded bottle as well.
"What's wrong?"
"Blankie," He whines again. Diluc sighs. He sets the bottle down on the counter as he passes by, which causes Kaeya to whine again and make grabby hands for it.
"Hold on, little blue, let me get your blankie first. Then we can refill it. Okay?" Kaeya huffs but goes quiet. He leans against Diluc's chest silently as he observes the other's movements, still managing to stay in his baby mindset. The storm outside is forgotten when he's in Diluc's arms, comforted by the presence of his big brother.
"Here you go. Is this one soft enough for you, little blue?" Kaeya grabs for the blanket Diluc holds up, hands clumsy while he tries to draw it closer to him. Diluc hums in satisfaction when Kaeya doesn't react in a negative way, instead trying to wrap the blanket around his brother's shoulders loosely.
Kaeya lets the blanket be maneuvered around him without complaints, babbling softly to Diluc about incoherent topics. Diluc still nods along and asks him small questions for him to babble in response.
"Here. More juice?" Kaeya nods, reaching excitedly for the bottle. Diluc laughs as he holds it out of reach, trying to pop the lid off. "Wait a sec, Kae. I have to fill it first," Diluc tuts.
Kaeya whines in protest, but he doesn't make a move to take the bottle from Diluc's hands. The noises he makes leaves Diluc on edge though, trying to tip toe around a potential tantrum.
"Here, do you want to watch me do this, little blue?" Kaeya hums around his own finger that he's raised to his mouth. Diluc looks down and moves it away, frowning slightly. "Don't do that, it's bad for your teeth." Kaeya whines again, hitting his head hard against Diluc's shoulder.
Diluc exhales on impact, but other than that it's fairly obvious to see that Kaeya's mind has regressed his body's strength as far back as it can go to match his mental age.
Diluc opens the fridge and pulls the juice bottles out, pouring half of one in the cup before filling the rest with water. Kaeya watches with half-discarded interest. He's tired, eyelids fluttering every so often. Being in Diluc's arms isn't helping, at all.
"Here you go, little boy blue. Let's go sit down now, hm? You look sleepy."
"Nuh-uh," Kaeya whines. He huffs before putting the bottle in his mouth. He glares up at Diluc for the suggestion of being tired for less than thirty seconds before he's leaning into his chest.
Diluc sits down on the couch and maneuvers Kaeya to be lying down, with his legs extended the full length of the couch and his torso cradled against Diluc's chest.
His eyelids flutter shut as he drinks from the bottle, falling asleep shortly after he reaches the half-way point. Diluc's arms don't move away from his brother, even when they're both clearly asleep.
Kaeya is the second one of the pairing to awaken, and when he does he's being held on Diluc's hip again. Diluc has changed into a cleaner uniform, and left Kaeya in his base pants and shirt. It's more comfortable than his original outfit, he'll admit.
"Morning," Diluc says.
"Morning?" Kaeya replies, shocked when Diluc looks at him with a questionable look.
"You're not... the little kid thing, anymore?"
"No. Why?" Diluc lets Kaeya put his feet down on the ground and stand again rather than being held. Kaeya obliges without a noise at all, but he still feels somewhat hurt with how quick his brother is to drop him off. He rationalizes that he's heavy, and he doesn't think about it past that.
"I was just wondering, if it carries through sleep."
"Sometimes. Usually when I'm with Albedo, not... It only happens in familiar atmospheres," Kaeya explains. He moves over to the counter and sits down on one of the stools.
"Oh."
"Sorry for, uhm, springing that on you. I know it's kind of weird for some people but it—"
"—Kaeya. Listen to yourself, quit talking down on yourself for it. It's a stress thing, is it not? You seemed more than happy doing it, and I was more than happy to oblige and take care of you. Stop worrying your head over it."
"Oh. What?" He looks at Diluc in disbelief.
"What?" Diluc looks up from flipping the pancakes he's been making. Kaeya watches then flip rather than make eye contact with Diluc.
"You didn't mind taking care of me?"
"No? Should I have?"
"No, no. I'm glad you didn't, I just... didn't expect you to care." That line shatters Diluc's heart into a mess on the floor. He stands silently for a second, struggling to sweep the pieces back into his chest without hurting himself.
"Why wouldn't I?" He turns to Kaeya, shutting the burners off to not burn the pancakes as he talks.
"I just– I thought, like, you didn't really... want me anymore. I told you, and you were all like, 'No, get away from me', and when I did stay away you didn't say anything. I just thought—"
"Kaeya," Diluc says softly. He watches the tears in Kaeya's eyes fall until he's crying softly, reaching out for his brother again.
"—I'm sorry," He says through a sob that wrecks his body. Dilucs hugs him close, head bent over to be closer.
"I'm sorry," Diluc says instead. "I am so, so sorry Kae. I never hated you. Never, ever, will I ever." Kaeya sobs harder into his chest, like everything he's pent up over years is coming out all at once.
"Wan' 'bedo," He whines through muffled baby talk and cries. Diluc nods, petting his hair softly.
"I'll call him after breakfast. Can we wait that long?" Kaeya nods, letting Diluc pick him up again and hold him on his waist.
"You're quite sweet when you're... little, is that it?" Kaeya nods in confirmation, turning his face to Diluc's coat. It's one of the ones with a fluffy collar, and instead of watching his brother cook pancakes for the both of them he giggles and pokes at the fur instead.
"'S silly," Kaeya says out loud.
"I think you're the silly one, out of the two." Kaeya devolves into giggles at Diluc's answer, kicking his feet out in excitement and nearly kicking in the cabinets underneath the counter. Diluc turns so Kaeya's feet are no longer a danger to his furniture as he sets the plates.
"'Luc, luc, guess what!!"
"What is it, little one?" Kaeya giggles again at the pet name, almost forgetting what he's saying.
"Oh! 'Bedo says I get a weasel stuffie, bu' only if I'm good!" He shares excitedly, grinning.
"Really? Does that mean I need to tell him you were extra good last night and today?" Kaeya nods quickly, almost resembling a bobhead. He makes a groaning noise to exaggerate his dizziness.
"Yes, p'ease. I wan' one!! Super bad."
"I don't know.... Will you eat your pancakes?" Kaeya nods, giggling again when Diluc sets him down on his stool again. Kaeya swings his feet as Diluc hands him his fork, careful to avoid the cabinets again.
Every time that he fails to, he looks up to Diluc with the most shocked expression Diluc's ever seen from him, and it makes both of them crack up. Kaeya eats almost all of his pancakes without protest, which Diluc takes as a strong win.
Everytime he has Klee over, meal times end up being two hours instead of half of one. Diluc is extremely grateful that Kaeya doesn't seem to have an issue with that.
"All done," Kaeya says. He pushes the plate away, slowly inching it towards Diluc.
"Good job, Kae. Thank you. Let me put these in the sink and we can call Albedo, okay?"
"Otay."
Kaeya watches over Diluc's shoulder as he calls Albedo, hooking onto Diluc's back. He called himself a human backpack when he did it, and Diluc had cracked a smile at it. Kaeya's over-the-top excited.
"Master Diluc?" Albedo's voice comes through the phone. It's altered a lot, messed up by grain and the regular pitch change.
"'BEDO," Kaeya shouts to the phone. Diluc hisses and raises a hand to his ear. Diluc can tell that Albedo likely felt the same way.
"Inside voices, kiddo," Albedo's voice filters through the phone, a slight sternness in his voice. It's almost unrecognisable, but Kaeya picks up on it with ease. Diluc wonders how much time they spend together, if little Kaeya knows him that well.
"Sorry," He whispers loudly into the phone. Albedo chuckles on the other side of the phone.
"You're alright. Here, can you let me and Master Diluc talk now? No interrupting, okay?"
"M'kay."
"Thank you," Diluc says before either of them can speak. Kaeya huffs at him and playfully glares, even if all of his intimidation tactics are ruined by his clumsiness.
"Master Diluc, have you been watching Kaeya all night?"
"Yes. Kaeya's been with me since he showed up at the tavern yesterday. He was stressed about the storm, I think."
"Was he behaving with the manners of a younger child?"
"He was little, yes." Kaeya unhooks himself from Diluc's shoulders, dropping down onto the floor to go run to the living room and mess with the blankets.
"Ah. He told you?"
"Yes. He also told me about a weasel stuffie?" Albedo laughs on the other side of the phone. It's genuine, uncontrollable laughter.
"Of course, the weasel plush. He's wanted it for about a month and he's been helping me to try and earn it. Did he mention it last night?"
"No, this morning during breakfast. He was too little to do much of anything last night." Diluc smiles to himself, fondness washing over him. Kaeya watches him judgementally from the massive mound of blankets he's created.
"Oh. How young?"
"He was a baby, for most of it. Rest of the time he was just a cranky toddler."
"'M not a cranky toddler," Kaeya chimes in from his spot across the room. He huffs and folds his arms, selling the point.
"Interesting. Would you be fine watching him for another hour? I need to finish this up, and then it'll take a while to get there."
"Of course."
"I'm staying?" Kaeya's head pops up next to the phone, listening eagerly to their conversation.
"Yes, you're staying for a bit." Kaeya pumps his arms in the air excitedly before taking off towards the living room again. Diluc watches him while he shares a few more words with Albedo, and then the phone is put back in its place on the wall.
"Luc?"
"Yes, Kaeya?"
"Can we watch a movie?"
"Do you still know where they are?" Diluc watches Kaeya tilt his head and think, one of his hands coming up to his chin as a joke.
"Mhm. Can I get one?? P'ease?"
"Are you babytalking your way into getting what you want?"
"No," He draws out. The mischievous grin answers for him, to which Diluc rolls his eyes.
"Yes, you may go get one of the movies. Please be careful with the fragile decorations in the hallway."
"I will," He shouts down the stairs as he takes off, running up them on all fours. Diluc looks around at the mess of blankets in the living room, paired with a few of Kaeya's trinkets lying across the floor. Diluc stares at them before sighing and picking them up, setting them down on the counter again.
Kaeya is much more enthusiastic when he's little, and Diluc has loved every second he's been able to take care of him again. It's been years since they last talked past aimed small talk, and with one proper conversation they managed to mend a few of the cracks in their relationship.
"Luc, I got it! Adeline helped me!!" Kaeya skips the last step, instead jumping down and running over to his side. It's one of the few horror movies they own, and Diluc takes a second to just glance at it.
It's Kaeya's favourite out of all of them, and Diluc can't say no to watching it, even if Kaeya tormented him with it all of their childhood.
"Alright. You can't talk over the entire movie, okay?" Kaeya nods excitedly, bouncing in place on the couch as he watches Diluc set the movie up.
It feels like old times, when they were both younger and Diluc was constantly doting on Kaeya. He was always trying to take care of him better than everyone else.
Which means that he might have been a little excited when Albedo showed up and Kaeya was reluctant to part from Diluc, begging to visit Diluc again. Maybe he was even happier when Albedo agreed and thanked him for doing such a good job at watching Kaeya.
But, he was definitely ecstatic when he was told that Kaeya's never regressed younger than a little kid, and certainly never to an infant mindset. The sense of pride that flooded him at those words never managed to fully leave.
"Bye bye, 'Luc," Kaeya waves before stepping out the door with Albedo. Diluc waves goodbye back to him, smiling when Kaeya starts up a fit of giggles again. Diluc's extremely happy, for the first time in years.