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1.
“In the event that Nezuko does attack a human, Kamado Tanjirou, as well as Urokodaki Sakonji and Tomioka Giyuu will commit seppuku in atonement.”
Tanjirou’s ears ring for one long, infinite instant. Then he stares across the stone garden at Tomioka-san, who looks straight ahead unwaveringly, as motionless as still water.
It’s like a pressure valve releasing; Tanjirou can’t find another way to describe it. The pulsing pain, the frantic frustration, the indescribable fear; he’s been holding them all back to listen, to find a way out of this corner they’ve been driven into, to do his utmost to safeguard Nezuko. Now, it all comes rushing out, tears spilling unbidden down Tanjirou’s cheeks.
It’s a heavy duty, to be responsible for a demon.
Nezuko is his sister. But Nezuko is also a demon, and in the eyes of the demon slayers she has no rights. In her stead, Tanjirou shoulders the weight of her life and the lives of those she might come to harm. It is not a burden, because Tanjirou would move the world for Nezuko, but it’s heavy, it is so heavy that it feels like it could crush his very soul if he allows himself to think about it too much.
He can only do it because he is the eldest son; more than that, he is the eldest sibling, Nezuko’s elder brother. Urokodaki-san has watched over Nezuko for two years, spending more time with her than Tanjirou did during his pre-selection training, and he has come to love Nezuko as a daughter.
But for Tomioka-san, who has absolutely no reason to put his life on the line, to shoulder part of that weight—
Tanjirou doesn’t think he can ever express out loud the multitude of emotions he feels at that moment.
And Tomioka-san does it again and again. He broke his stillness to shout at the scarred Hashira holding Nezuko’s box, giving Tanjirou a chance to find the line of opportunity and smash his forehead down onto the offending demon slayer’s skull. And although Tanjirou can’t see, can barely breathe, he knows it’s Tomioka-san who restrains the serpent Hashira, allowing Tanjirou to lift his head and scream out Nezuko’s name, to catch her attention, to give her that precious second to regroup and gather her self-control.
Nezuko can do it, she can ignore the call of human blood and stay human in all the important ways that matter. They just have to give her to opportunity to prove it.
And Tomioka-san does, in defiance of the rules, in defiance of his fellow Hashira.
The Hashira, the Pillars of the Demon Slayer Corps. Tanjirou doesn’t know the other Pillars, but Tomioka-san more than deserves the title. He’s strong, not just in battle but in his convictions, and he gives his support to those who need it most, silently, unconditionally.
Tomioka-san probably doesn’t want any fuss or loud declarations of gratitude. So Tanjirou will continue doing what he’s always done – train hard, fight demons and protect humans with Nezuko at his side, and search for a cure. He’ll make the most of Tomioka-san’s support, of his trust.
And more than anything else, Tanjirou is glad that Tomioka-san is here, that he is not doing this alone.
2.
“Tomioka-san.”
Giyuu pauses. He’d hoped to slip away from the Ubuyashiki estate without confronting any of his fellow Pillars, especially after the raucousness that was the Kamado siblings’ supposed trial. But Kochou moves as delicately and unobtrusively as the butterflies she so favours, and she’d been waiting just outside the estate grounds, hiding herself until he passed through the gates.
“Kochou,” he says evenly. He’d piqued her annoyance on Natagumo mountain; despite her sympathy towards Tanjirou, Giyuu knows whatever words she has for him now will bite.
“Tomioka-san,” Kochou says once more, her smile never changing. “Won’t you come to the Butterfly Estate to check on the Kamado siblings?”
Giyuu stifles his automatic rejection, but something must have given him away, because Kochou’s smile deepens.
The silence stretches out between them.
“No,” Giyuu finally says, since she already knows. He doesn’t give an excuse; it’s rude to say that he would never willingly walk into her territory without being ordered to (although he’d choose Kochou over Shinazugawa or Iguro, and even over Uzui, who is just too loud), and saying anything about Tanjirou or Nezuko would likely just give her more rope to hang him up with.
Kochou sighs. “That’s not very friendly, Tomioka-san. And here I thought you’d finally become more sociable.”
Her tone is honeyed, but like the wisteria poison she is renowned for Giyuu would not be surprised to find himself wincing over the fine sting of her words hours later.
“I have duties to attend to,” he counters. There – after all that griping about Giyuu breaking his responsibilities as a demon slayer, surely none of them can argue with that.
“Now, don’t sulk,” Kochou chides. “It goes against the most important precept of being a demon slayer, to help a demon; you can’t blame us for reacting the way we did. And it worked out in the end. Thanks to Oyakata-sama, none of you are getting punished; not Tanjirou-kun, or Nezuko-san, or you.”
That gets more of a reaction out of Giyuu. “I am not sulking.”
“Oh dear, you still haven’t realized, have you? Well, I won’t argue with you.”
Giyuu decides that discretion is the better part of valor and simply walks away. Maybe if he moves quickly enough, Kochou won’t have enough breath to pester at him; he doesn’t hold out hope that he can truly outrun her, if she decides to chase him down.
“Two years ago, you said, when I asked why you were helping a demon. Two years ago, that’s when it started.”
Giyuu continues walking.
“And two years ago, that’s when you changed. Remember the Matagi girl and her father? You were worried in your own way; you’d changed, then. I wonder, was that before or after you met Tanjirou-kun?”
Giyuu’s feet halt without conscious thought. It turns out Kochou doesn’t need to keep up, not when she can stop him with her words alone.
On some days, Giyuu feels that it was inevitable that he created the Breath of Water’s Eleventh Form. Urokodaki, his master, had told him to keep his heart as steady as a water’s reflection; Giyuu took that advice even further, forcibly instilling stillness where once was turbulent, choppy waves. Giyuu is a student of the Breath of Water, and his waters run deep. There, he smothers his anger and his anguish and his helplessness, and he stands upon that calm reflection, ignoring that tiny but ever-present part of him that wishes to drown once and for all with Sabito and Tsutako-nee-san. He’d survived that way, becoming strong enough to be the Water Pillar.
It’s become the founding rule of his world: Pillars never crumble. Giyuu never wavers.
But that’s no longer true.
Like Kochou reminded him, Giyuu has changed. He has allowed his heart to be swayed, he’s made exceptions, and for all that it is for one boy, for one pair of siblings, Giyuu isn’t sure that he won’t be swayed again in the future. And there is no guarantee that he’ll make the right decision a second time.
Perhaps Giyuu’s suspicions are true after all – he is not worthy of becoming the Water Pillar.
“‘There are things that must be supported. So the Pillars must act as Pillars.’ That’s what you said to me, two years ago.” Kochou flashes into place beside him, quickly enough that her hair dances around her face, even if the air barely stirs around her. “Tomioka-san, I hope you still believe that.”
“Kochou—”
“It’s all right if you don’t want to face them. But unlike Urokodaki-sama, I won’t be sending you updates by crow.” Kochou tips her head to the side, smiling. “Well, if you want to know how Tanjirou-kun and Nezuko-san are doing, you know where to find them. At least for now. Going by Tanjirou-kun’s resolve, he’ll be back in the field soon enough.”
She takes off in a single bound, her patterned haori flaring out like the wings of a delicate butterfly. Her voice floats back down to where Giyuu is standing. “Until the next Pillar meeting, Tomioka-san.”
Giyuu stands there, unmoving, for a very long time.
3.
Dear Tomioka-san, Tanjirou pens onto paper, and pauses to gather his thoughts.
In the days after the battle of the Red Light District, Tanjirou makes it a habit to sit down for a quiet hour of letter writing, after the day’s completion and before the moon’s rise. As a coal burner’s son, he is used to resting and rising with the rhythm of the sun; as a demon slayer and Nezuko’s brother, he’s adjusted to nocturnal hours, conserving his strength during the day; while waiting for Nezuko to rouse, he now takes time to keep in touch with the important people he’s met along his journey – Urokodaki-san and Senjurou-kun, Uzui-san during his recovery, and the ladies from the Red Light District who befriended him despite knowing parts of his truth.
And of course, there is Giyuu-san.
Giyuu-san never responds, but that doesn’t stop Tanjirou from sending the letters. It doesn’t bother him; the quiet is part of Giyuu-san’s nature, and the profound silence is comforting. After all, Giyuu-san is the demon slayer who met Tanjirou once on a snowy mountain, did not hesitate to defend the Kamado siblings yet again the second time they met at Natagumo mountain, and quietly, unobtrusively betted his life on Tanjirou’s belief in Nezuko in the two years between.
Giyuu-san’s actions speak louder than his words; to Tanjirou, they’ve always proclaimed how truly kind Giyuu-san is.
Only the strong can afford to be kind, Tanjirou thinks; thankfully for them all, Giyuu-san is one of the strongest.
The snap and hiss of a match striking breaks Tanjirou out of his thoughts, and he glances up, blinking as Nezuko lights the table-top lantern. She flicks out the match and turns to stare at Tanjirou with mildly accusing eyes.
“Ah, sorry Nezuko.” Tanjirou scratches sheepishly at his hair. “I got lost in my thoughts; I’m not writing in the dark, I promise.”
That appeases Nezuko; she skips around the table to settle at his side, staring down curiously at the letter.
“I’m writing to Tomioka-san,” Tanjirou says, setting his pen down to gently pat Nezuko’s head. “I got as far as ‘Dear Tomioka-san’ and then I got lost thinking of what to write to him about next.”
There are dried splotches marring the pristine cream of the paper where the ink had dripped from Tanjirou’s pen; Tanjirou sighs, because of course Giyuu-san never complains, but he deserves to get Tanjirou’s best, not an untidy letter that speaks of Tanjirou’s distraction.
Nezuko makes a quiet noise in her throat, pointing at Giyuu-san’s name on the paper before tilting her head to stare up at Tanjirou. Her eyes ask the question she can’t voice; Tanjirou understands her, through a combination of intuition, his sense of smell and his incredible familiarity with her.
“You’re right. Zenitsu, Inosuke, and even Shinobu-san is Shinobu-san.” Tanjirou laughs. “So, why is Tomioka-san Tomioka-san, and not Giyuu-san?”
Nezuko stares at him expectantly; she’s of like mind as Tanjirou. Giyuu-san, who has given so much to them both, deserves to be regarded as close as family, without the formality of last names separating them.
Tanjirou touches light fingers to the characters he always writes with meticulous care, even when the rest of his letter descends into their usual flowing messiness. “Tomioka-san seems like the type of person who keeps his dignity even in battle. I figured I’ll only try using ‘Giyuu-san’ when I see him in person, so he’ll have a chance to protest. Doing it in a letter he can’t respond to directly doesn’t seem very fair, does it?”
The fire dances in Nezuko’s eyes, and she nods once, settling her head back on Tanjirou’s shoulder. Tanjirou smiles down at her, and carefully tears off the splotchy part of the paper so he can start his letter anew.
Dear Tomioka-san, Tanjirou pens once more onto paper, but in his heart, it’s Dear Giyuu-san.
4.
It takes the space of three breaths for Tanjirou to switch from calling out “Tomioka-san!” to “Giyuu-san!”
It surprises Giyuu, but a moment later Tanjirou declares that he’s coming right into the building despite Giyuu’s lack of a response, and Giyuu is so confused that he doesn’t visibly react when Tanjirou slides the door right open, his smile somehow seeming even brighter than the sunbeams lighting up his red hair.
Giyuu has been the Water Pillar for many years, and in all that time none of the slayers in his territory have dared to be that presumptuous. Tanjirou, on the other hand, just sits down close – too close – and jumps straight into a recounting of the Pillars’ training program.
It’s not that he’s purposefully breaking convention; instead, it’s more that convention simply doesn’t exist for Tanjirou. He follows Giyuu around, talks all the time, asks questions, stays close, and it’s always Giyuu-san, Giyuu-san, Giyuu-san—
—and Giyuu’s heart wavers and wavers and wavers, lost.
It takes a conversation on a wooden bridge spanning a gentle river and the memory of a slap for Giyuu to realize that not all changes are bad. Giyuu’s element is water, and like water he tends to follow the path of least resistance. But Tanjirou is like the sun, bold and brilliant with his own brand of magnetic gravity; he pulls Giyuu out of inertia, into angry outbursts, into pledging his life on Tanjirou’s strength and Nezuko’s humanity, into remembering the most painful but poignant parts of his past.
Tanjirou pulls Giyuu along with him, into noodle shops and walks around the Ubuyashiki estate and peaceful basking in the sun, and Giyuu knows they make an odd sight: Tanjirou with his one crutch and wrapped up ankle, all bright chatter and youthful exuberance, and Giyuu following closely behind, tall and stoic and seemingly docile. He can feel the stares, the murmuring undertone of confusion and condescension; Giyuu is used to it, to people not understanding or being able to relate to him.
Still, Giyuu thinks he likes this better. It is better to be seen as foolish, obediently trailing after Tanjirou like this, than to be deemed a fool on his own.
And soon, the sound of his given name in Tanjirou’s voice becomes a pleasure – an audible reminder that to at least one person in the world, Giyuu is cherished, not hated.
5.
Tanjirou hasn’t felt this nervous in a long time.
He has faced down powerful demons and stood on trial for his sister’s life, but those circumstances are different. Those are moments of life and death, where he has to push away the panic to deal with the very visceral present; now, standing in front of Giyuu-san’s part-time abode near the Ubuyashiki estate, Tanjirou has plenty of time to think of how very much he wants this to go well, and all the possible ways it can go wrong—
“Tanjirou,” Giyuu says from behind him, and Tanjirou’s heart leaps into his throat, startled.
—starting, of course, by almost dropping the container of food in his hands all over the floor.
Fortunately, years of training have stifled all of Tanjirou’s instinctive clumsiness; he catches himself, and then he whirls around, light on his feet, exclaiming “Giyuu-san!” in the same breath.
Giyuu stares down at him seemingly impassively, but Tanjirou knows better. Giyuu exudes both fondness and exasperation, although his voice betrays neither as he says, “Your reflexes are better than that. I shouldn’t have been able to catch you off-guard.”
“That’s because it’s you, Giyuu-san,” Tanjirou says without thinking. “I don’t need to keep my guard up with you; I trust you!”
Giyuu doesn’t answer, just steps past Tanjirou to slide the doors to his residence open; Tanjirou can smell the bloom of startled warmth, however, and he trails happily into the house, assured of his welcome.
“I’m training with Kanroji-san right now,” Tanjirou says, walking right into the kitchen, where Giyuu is already in the middle of making tea. Tanjirou seats himself at the table, setting his container carefully down; it’s funny, how comfortable and calm he feels in Giyuu’s presence, when earlier he’d been jittery and nervous. “Her flexibility exercises can take quite the toll on the body, so she gives us plenty of breaks to rest.”
He chatters on about his training with Uzui and Tokitou, and although Giyuu doesn’t respond, Tanjirou knows he’s listening closely. Giyuu doesn’t like to talk, and Tanjirou doesn’t mind taking up the task of filling in the silence; he likes it, that he can do something for Giyuu, even if it’s something small like this.
Soon enough, Giyuu sets a cup of tea – high grade sencha, light and fragrant – in front of Tanjirou, and sits down across from him, still quietly listening.
Tanjirou smiles his thanks, and wraps his hands around the cup, savoring the warmth. “I’ll be heading Iguro-san’s place next, but I’m really looking forward to training with you soon, Giyuu-san!”
This time, Giyuu doesn’t shoot down his request. Instead, he takes a slow sip of his tea and says, “You need to go through Shinazugawa and Himejima’s training sessions first.”
“Of course,” Tanjirou chirps, because to quote Zenitsu, he’s “one of those maniacs that enjoys hellish training, what the heck is wrong with you?!” But there are so many good reasons to enjoy the special Pillars’ training sessions – Tanjirou can feel himself getting stronger, he gets to learn and experience a variety of fighting styles, and he gets to spend time with people he likes. “But it’s something to look forward to all the same.”
It doesn’t quite make Giyuu smile, but Tanjirou fancies that his eyes are a little lighter – that maybe Giyuu is looking forward to training together with Tanjirou too.
They drink their tea peaceably together for another few breaths, and then Giyuu tilts his head, indicating the container sitting between them.
“Oh!” Tanjirou’s hand flashes out to touch the lacquered sides. It still radiates heat and he breathes out a sigh of relief.
“Kanroji-san lets me use her kitchen when she’s not using it, and I wanted to make this for you.” He gets to his feet as he speaks and collects a pair of chopsticks and a spoon from the counter. “It took me a long time to figure out what you like, even with my sense of smell, and I know I won’t be able to visit you as often once I leave Kanroji-san’s residence. I didn’t have time to test out the recipe, so I hope it still tastes good.”
He’s rambling, Tanjirou knows he’s rambling, but some of that nervous jitteriness is back in his bones. He holds out the chopsticks and spoon; Giyuu takes them with an air of bemusement, although his eyes are very calm and steady, as if to reassure Tanjirou that whatever it is, he’ll like it.
Tanjirou twists the top off the container before he can think about it too much, and lets Giyuu judge the dish for what it is.
The aroma of savoury saltiness wafts into the air, and Tanjirou looks down instead of watching Giyuu’s expression. Orange-pink slivers of salmon and pale slices of radish swim in a warm broth; it looks and smells quite appetizing to Tanjirou, but then again, he’s not the one that’s going to eat it.
Giyuu is very, very quiet, even for him, and Tanjirou jerks his gaze up. He doesn’t have quite enough time to worry, however; Giyuu dips his chopsticks in, places a delicate piece of salmon and a slice of radish on his spoon, and eats the mouthful neatly.
It takes Tanjirou a moment to realize he’s staring, and at Giyuu’s mouth, no less.
Giyuu doesn’t seem to notice; he takes a spoonful of the broth this time, and there’s something else spiking in the air now – the scent of pleasure, rich and heady.
“It’s delicious,” Giyuu says simply, and Tanjirou forgets about everything else in that moment.
“So I got it right?” Tanjirou asks, delighted. “Simmered salmon and daikon is your favourite food?”
Giyuu looks up then, meeting Tanjirou’s gaze straight on, and Tanjirou feels his heart leap into his throat once more, although this time it is not in shock. Giyuu’s eyes are often piercing, but like the colour of the ocean they are infinitely changeable; now, they are gloriously blue, but the sight of them has nothing on the very tender, very brilliant smile gracing Giyuu’s lips.
“Yes,” Giyuu says. “It’s perfect.” Then, he holds out his pair of chopsticks. “Have some with me.”
Tanjirou could tell him that he’s already had more than his share – nervous in the kitchen, taste-testing the dish as it cooked because he only has time to do this once. He could say that he cooked this dish especially for Giyuu, so he should have it all. But Tanjirou doesn’t, because there’s a special joy in making food for the people he cares about, in nourishing them with his own hands and effort, and there’s another kind of joy in sharing that meal, in eating together.
Tanjirou won’t deny Giyuu that.
He takes the chopsticks, and his acceptance makes another smile flash across Giyuu’s face – not quite as brilliant, but just as precious all the same. Tanjirou’s heart pounds in his ears, because he knows just how rare Giyuu’s smiles are—
—but what is most startling of all is how much Tanjirou wants to keep teasing that smile out, to be the reason it appears again and again.
That’s a thought for another time, however, for Tanjirou to sort out his feelings; now, there is Giyuu, a shared meal of salmon and daikon, and a moment of peaceful happiness to bask in.
And with the knowledge that Nezuko is safe with Urokodaki, that his friends are training hard with the other Pillars – right now, Tanjirou could not ask for anything more, not with Giyuu here with him, still quietly smiling.
6.
When the Upper Moon Three blasts him through countless walls and rooms, Giyuu only has space for one emotion over the searing pain and his own concentrated efforts to catch himself – he is incredibly grateful that he got to witness Tanjirou’s strength before he’d been sent flying.
Normally, when Giyuu gets separated from the lower-ranked demon slayers in battle, he always nurses a quiet fear that it would be the last time he’d see them alive. He braces himself for their deaths even as he fights to get back to their sides, to protect them; the lower ranks fall so easily, even as the Pillars endure.
But not this time.
Tanjirou is so much stronger now, almost Pillar-ranked in power, but more than that Giyuu trusts in his tenacity and his resilience. Giyuu has time to reorientate himself, to breath deep and channel healing to the slashes in his back, to prepare himself to leap back into battle.
There is also another emotion rapidly taking up space in his heart, filling the sudden clear clarity of his mind. For the first time in a long time, Giyuu is angry, truly angry. Because he’s had a taste of happiness, of pure bright joy after years of – at best – peaceful serenity, and he knows it’s in no small part due to Tanjirou. Oyakata-sama, Kochou, the fact that Tanjirou is fighting an Upper Moon right at this moment – the anger rushes through Giyuu’s body like liquid fire, a simmering kinetic energy that feels like it could burst out of Giyuu at any moment.
He covers the long distance in an instant, has the fraction of a second to judge the situation and the angle and the timing, and slices the Upper Moon’s arms clean off. Tanjirou rolls clear, his blade still in one piece, and Tanjirou himself is whole and mostly hale, and confident enough in the situation to call out Giyuu’s name.
Giyuu doesn’t look at Tanjirou, keeps his attention firmly on the very dangerous creature before them. Because he already knows it’ll take the both of them to kill this Upper Moon, and it’s Giyuu’s turn to do his part.
“I am angry now,” he tells the Upper Moon, because he is. He is angry, but above that, Giyuu is determined. He would die to protect Tanjirou just as Tanjirou would undoubtedly protect him in turn, but before it gets to that point, Giyuu will fight with every inch of his being so they can both get out alive.
Because Giyuu wants more days in the sun, more shared meals with Tanjirou and his fellow Pillars, more time to live. He wants to see Nezuko turned back into a human, wants to see how radiantly Tanjirou can laugh once that all-consuming worry is finally put to rest.
He hears Tanjirou breathe out his name, “Giyuu-san,” surprised; feels heat burning over his left cheek.
Giyuu breathes, and attacks.