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There was a particular chill in the early-morning air that day, as if the winter breeze was trying to sneak into every crevice of the Demon Slayer Corps estate and remind its residents of the season’s icy sting. You found yourself clutching the edges of your haori tighter, trying to gather any lingering warmth from your surroundings. You had risen before dawn, as usual, determined to run through your sword drills and breathing exercises. At first glance, the day seemed like any other: the soft golden light turning the horizon a pale peach, the crows perched on wooden beams as they let out their raspy cries, and the silence of a world not yet fully awake. Yet in your chest, the excitement vibrated like a plucked string. Today was special—February 8th, your mentor’s birthday.
Not that Giyuu Tomioka, the Water Hashira, had announced it. In fact, you strongly suspected he would never mention such a personal detail voluntarily. He was far too reserved and stoic to bring up anything as supposedly trivial as his own birthday. But you, eager and bubbly Tsuguko that you were, had your ways. The day before, you had overheard Mitsuri Kanroji squealing with delight over “this wonderful Western tradition.” She had been explaining to you, with her trademark enthusiasm, that in some places across the sea, it was common to give presents, or even cake, to someone on their birthday.
You had latched onto the idea instantly. After all, Giyuu was not one to celebrate. You had never known him to indulge in anything remotely self-centered. Birthdays, you suspected, would be no exception. As his Tsuguko, his steadfast student who tried so desperately to connect with him, you could think of no better opportunity to break through that quiet shell than by surprising him on this day he so persistently pretended didn’t matter.
Tucking a strand of hair behind your ear, you marched, well, you attempted to march, across the courtyard in search of your teacher. Unfortunately, your enthusiasm was a bit too strong; the toe of your sandal hooked beneath an uneven stone, launching you forward in a not-so-graceful tumble. Flailing your arms like a startled bird, you narrowly avoided face-planting against the cobblestones. A small yelp escaped your lips, but you managed to catch yourself before meeting the ground in an embarrassing collision. You paused for a moment, heart hammering. Then, in typical you fashion, you pushed onward with an irrepressible grin.
“Tomioka-san!” your bright call echoed off the wooden walls.
No response. The large estate building, framed by the skeletal silhouettes of winter-bare trees, remained hushed. You knew, however, that he had to be somewhere around, perhaps by the pond, or in the training hall polishing his blade. The man had an uncanny ability to fade into the background if he didn’t want to be noticed. But as his student, you had learned a few tricks of your own.
After ensuring your footing was secure this time, you headed around the side of the building and toward the training grounds. There, framed by the soft morning light, he stood: posture upright, sword in hand, every inch the Water Hashira. His attention was fixed forward, eyes narrowed in intense concentration as he practiced the fluid arcs of Water Breathing forms. Each slash and pivot seemed to move with the grace of a stream cascading over smooth rocks, no wasted motion, no hesitancy. It was mesmerizing to watch.
Yet as you approached, you could practically sense the tension in the air. He must have heard your footsteps, for he concluded his practice with a final slash, then turned his head slightly, acknowledging you with the faintest tilt of his chin. That was Giyuu’s version of a greeting, unspoken, subtle, yet polite enough.
“Good morning, Tomioka-san!” you chirped, bowing swiftly before lifting your head, still wearing that irrepressible smile.
“Good morning,” he responded in that gentle monotone, voice barely audible over the shifting wind.
Here was the tricky part. You doubted he would respond favourably to a direct question along the lines of, “So, you have a birthday today, right? Any special request?” He would more likely vanish in the swirl of winter air or simply stare you down until you changed the topic. Instead, you decided to approach this with cunning, or at least the closest approximation of cunning your enthusiastic, clumsy self could muster.
“You look especially focused today,” you started, feigning casual interest. “Any reason for the extra dedication?”
He sheathed his sword in one smooth motion, turning to face you fully. Though his expression remained unreadable, you detected a hint of caution in his eyes, like he already sensed you were up to something. “I always train with dedication,” he replied simply.
An awkward silence threatened to settle, but you refused to let it linger. Mustering every ounce of your unstoppable energy, you pressed on. “Of course, you do,” you agreed hurriedly. “But, uh... sometimes it feels like you... you know... put more heart into it than other days. Maybe... maybe on days that mean something special to you?”
Your attempt was clumsy at best, but you had never been known for subtlety. Even now, your face warmed in an anxious flush. Giyuu narrowed his eyes, not in anger, but in that disconcerting way he had of studying you, as if calculating whether to continue the conversation or shut it down.
“I’m not aware of any special meaning,” he answered at last, stepping forward. He brushed past you gently on his way to the wooden rack where he often kept his sword. “I train because it’s my responsibility.”
You resisted the urge to sigh dramatically. Instead, you followed him, hoping to glean just a crumb of information. “Right, right. Responsibility is important.” Your tone was sunny, if a bit forced. “But it’s also important to... take time for yourself, is it not?”
He replaced the sword, adjusting it carefully on the rack, then glanced at you over his shoulder. “What do you mean?”
Oh, your heart panged at that question. It was your personal mission to show him that there was more to life than fighting demons and brooding in lonely corners. You fidgeted with the hem of your uniform, forcing a bright grin. “Well, I... I thought maybe you’d have something you wanted. Something that might make training easier. Or maybe something that would bring you even a little joy. And if, hypothetically, you were to receive... a token of appreciation, one that might align with your personal interests, what would that be?”
Giyuu stared for a long moment. You became all too aware of how your question sounded. It was about as subtle as a drum parade, but there was no turning back now.
He finally answered, voice as neutral as always, “Why do you ask?”
Blood rushed to your cheeks, and you scrambled to salvage the conversation with some believable half-truth. “I... uh... wanted to improve as your Tsuguko. If there’s some piece of equipment or supplies you need, it might help me better fulfill my role. Right? So I can help you train, or maybe keep the estate in better order, or... anything.”
He studied you once again with that quiet, unwavering gaze. Then, with a slight shake of his head, he walked past you, heading toward the estate’s inner corridors. His voice floated back to you, calm as still water: “I don’t need anything.”
And that was that. You could have hopped on one foot waving your arms in the air, and it wouldn’t have changed his answer. Tomioka Giyuu had no interest in telling you what he wanted, or perhaps he genuinely believed he desired nothing. But you, with the unstoppable force of your own determination, refused to let his stoic reticence crush your plan.
Later that day, you snuck into the bustling kitchen area, where several Kakushi and Corps members were busy preparing meals. Warm steam fogged the windows, and the delicious aroma of simmering miso soup and fresh rice hung in the air, filling your senses and making your stomach grumble. You weaved through the chaos with as much grace as your clumsy feet would allow, only tripping over a stray wooden spoon once, which, for you, was record-level dexterity.
On a small counter near the back, you found exactly who you were looking for: Kanroji Mitsuri herself, the Love Hashira, joyfully stirring a pot of sweet bean soup while humming a cheerful tune. Her pink-and-green hair swayed in twin braids, and the aura of warmth and tenderness around her was almost tangible.
“Mitsuri-san!” you called, careful to keep your voice low enough so as not to startle her into spilling anything. She turned to you with an eager sparkle in her eyes.
“Ah, hello!” she greeted, stepping away from the pot and wiping her hands on a floral-print apron. “I was just perfecting a new recipe for sweet bean soup. How can I help you?”
You fiddled with your fingertips, the tension in your shoulders melting in Mitsuri’s presence because, truly, who could stay tense around her? “I was hoping I could ask about that Western tradition you were mentioning before. The one about birthdays and presents?”
Her eyes lit up with renewed excitement. “Oh! Of course, of course! It’s such a marvellous concept, don’t you think? To have a day dedicated to celebrating someone’s existence and giving them gifts and sweets? It’s so endearing!” She clapped her hands together, the wooden spoon in her grip knocking lightly against her wrist.
Nodding vigorously, you blurted out, “Exactly! I... well, it’s Tomioka-san’s birthday today, and I... I want to give him something. I thought maybe a present. Or, and don’t laugh, but maybe a cake. But I have no idea what kind of present he would like.”
Mitsuri clutched her wooden spoon as if it were a precious heirloom, eyes shimmering with teary delight. “That’s so sweet of you! Tomioka-san needs more recognition. He’s so hardworking and so quiet all the time. It’s wonderful that you want to surprise him.” She pouted, pressing a thoughtful finger to her lips. “But yes, finding out what Tomioka-san likes might be a bit tricky.”
You huffed, shoulders falling. “I know. I tried asking him directly, but he wouldn’t budge. It was like trying to get a fish to climb a tree.”
She giggled. “Why not think about what you already know? Tomioka-san is calm, reserved, and very devoted to his swordsmanship. Maybe he prefers simple things, something practical and minimalistic.”
A lightbulb flicked on in your mind. “That’s it,” you whispered with mounting excitement. “He won’t tell me, but I can make a guess. He likes fish, doesn’t he? I’ve seen him by the river sometimes, just... gazing at the water. He also enjoyed that grilled salmon once after a mission, though he hardly said a word about it.”
Mitsuri tapped her chin, following your train of thought. “Could you do something related to that? Maybe a new fishing rod or some kind of bento with fish?”
“I suppose.” Your brow furrowed, remembering the quiet contentment Giyuu had shown around water. “But I want it to be more than just fish. I want it to feel like a real celebration.”
Mitsuri’s face brightened with an idea. “How about you bake him a Western-style fish-shaped cake? Or... or something that combines the Western tradition with his known preferences!”
You grinned, an enthusiastic clap of your hands startling a Kakushi passing by with a tray of vegetables. “That’s brilliant! I could try to make a small cake shaped like a koi or a salmon. And maybe I’ll also give him a practical gift, like a new set of koi-decorated chopsticks. Something modest but thoughtful.”
“Perfect!” Mitsuri beamed, leaning forward. “If you need help with the recipe, I’ve been practicing Western-style baking. I even have a small recipe for a butter sponge cake that’s so fluffy and sweet. It might need some shaping skills for the fish design, though.”
Your stomach twisted nervously. You were known to be a bit... reckless in the kitchen. But your determination overshadowed your fear, and you straightened your posture, voice brimming with resolve. “I’ll do it! If it means surprising Tomioka-san, I’ll figure out a way to decorate it. Even if it turns out looking like a lopsided catfish, I won’t give up!”
Mitsuri clapped her hands, looking near tears from joy. “Oh, this is so exciting! I’ll help you, just call me when you’re ready to start!”
You nodded eagerly, feeling a surge of warmth fill your heart. So that was settled: a special fish cake and a small, practical present. You vowed to keep it simple and not go overboard, lest Giyuu recoil from any perceived extravagance. This was about making him feel valued, not overwhelmed.
Of course, baking a fish cake was easier said than done, particularly given your inherent clumsiness. By the time the afternoon sun was high in the sky, you and Mitsuri were elbow-deep in flour, sugar, and butter. The small estate kitchen you had commandeered for this mission boasted a single large oven, an innovation introduced by a traveling Western merchant. You had never imagined yourself using it for a fish-themed pastry, but here you were, determined and covered in a fine dusting of flour.
“Careful, careful!” Mitsuri squeaked as you poured batter into an improvised fish-shaped mould you had carved out of a metal pan. “It’s hot, so watch your fingers!”
“I know, I know,” you muttered, biting your lip as your hands trembled with anticipation. You succeeded in only spilling a little of the batter along the edges. That was a victory in your book.
Time seemed to slow to a crawl as the batter baked, the sweet aroma wafting through the air, brightening the kitchen and drawing a handful of curious onlookers. You chased them away before they could ask too many questions. The last thing you needed was Giyuu finding out about your plan from a gossiping crow or an inquisitive Kakushi.
Finally, the cake was done, golden brown and puffed up in the semblance of a fish form, albeit a slightly plump fish. You and Mitsuri carefully removed it from the mould, cheering softly at your success. It was not the most elegant shape, and one edge looked a bit too rounded, but the moment you pressed a finger into the cake’s surface, you felt the springy softness and knew this treat would at least taste good.
“It’s adorable!” Mitsuri exclaimed, clasping her flour-coated hands together. “Now for the icing.”
That proved to be an adventure in itself. Icing sugar, whipped cream, and colourful decorative bits soon covered the countertop like fresh-fallen snow. Mitsuri guided your trembling hands as you painstakingly piped an outline of scales along the cake’s top. Your clumsiness reared its head a few times: you almost dropped the piping bag, and you smeared a dollop of frosting across your cheek. Mitsuri giggled gently each time, and you returned her laughter with a sheepish grin.
Eventually, you stood back to admire your collective efforts. The cake was undeniably fish-like, with little white scales and fins piped in icing, a dab of jam for the eye, and a faint dusting of sugar to give it sparkle. You could almost imagine it shimmering underwater. You felt a wave of relief and pride flood through you.
“It’s perfect,” you breathed, pressing your sugar-covered fingers to your chest.
Mitsuri nodded in agreement, eyes shining with encouragement. “I’m sure he’ll love it.”
But there was more to do. You had the gift portion of your plan to finish. You quickly retrieved a small cloth-wrapped bundle from your room, a set of elegant, dark-blue chopsticks carved with delicate koi patterns near the top. It was practical and understated, hopefully something Giyuu would appreciate without feeling it was too flashy.
For a moment, you could only stare at the gift, imagining his reaction, would he blink in confusion, remain stoic, or perhaps, if you were lucky, let the corners of his mouth tilt into the barest hint of a smile? The thought electrified you.
When the cake had fully cooled and was properly decorated, you and Mitsuri carefully placed it in a wooden box for safekeeping, nestling it in a bed of soft cloth to protect the delicate details. Then, holding your breath, you slowly slid the lid shut.
“All set,” Mitsuri declared, folding her hands in front of her apron. “When are you going to give it to him?”
You swallowed hard, nerves flaring unexpectedly. “Tonight. When he’s done training, maybe. Or after dinner.”
Her eyes danced with excitement as she patted your shoulder. “Good luck! And happy birthday to Tomioka-san!”
You found your mentor in the late evening, as planned, sitting quietly by the estate’s engawa. The night sky outside stretched wide and tranquil, speckled with distant stars. A dim lantern’s glow illuminated Giyuu’s face, and you noticed, not for the first time, how a subtle sense of melancholy always seemed to cling to his features whenever he found a moment’s peace. It was like a lonely shadow draped across his expression.
Feeling your heart race, you quietly slid the door open and stepped out onto the wooden walkway. The wooden planks creaked under your weight, drawing his attention, but he didn’t turn fully—only cut his gaze toward you with the faintest motion of his head.
“Tomioka-san,” you said softly, your voice wobbling with a mixture of excitement and nerves. He offered a silent nod of acknowledgment.
Emboldened by the hush of the night, you settled beside him, the wooden box and cloth-wrapped gift held in your arms. Now or never, you told yourself. Take a breath. Take the leap.
“I... wanted to say something,” you began, staring at the bright moon overhead to summon some courage. “I know you don’t talk much about yourself or expect any fuss, but... well, I learned from Mitsuri-san about how birthdays are celebrated in the West. People exchange gifts or have a cake, to honor the fact that the person was born. And today is your birthday, Tomioka-san.”
You sensed his body stiffen beside you. He inhaled slowly, as though preparing to protest, but you forged ahead before he could utter a word. “I know you said you don’t need anything. But I... wanted to give you something anyway, to thank you for being my mentor. And for... for just being here, I guess. I appreciate you, even if I don’t always say it right.”
His gaze slipped from your face down to the box and bundle in your hands. You could practically see the internal conflict in his eyes, an unease at being the centre of attention. Still, he didn’t reject you outright, and that was enough to calm your racing heart.
You carefully set the items before him on the engawa. First, you placed the gift-wrapped chopsticks in his lap. “Here. For meals during missions or at home. I noticed your old pair was starting to wear out.”
He untied the small knot of cloth. The lantern light glinted off the polished wood of the chopsticks, highlighting the subtle carvings of koi fish along the upper half. Giyuu stared at them for a few silent seconds, expression unreadable. You felt your own breath catch, worried you had misread him. Then, slowly, he brushed his fingertips over the carved patterns.
“They’re... nice,” he said quietly.
Relief washed over you like warm water. That was as close to “I like it” as you might ever get from Giyuu. Encouraged, you slid the wooden box into his view. “And this... is a birthday cake. A Western-style tradition.” Your cheeks warmed, and you found yourself babbling. “I tried to shape it like a fish, because... you... um... you like fish. I made it with Mitsuri-san’s help, so it’s edible, I promise!”
With careful, deliberate motions, Giyuu lifted the lid. Inside, the fish-shaped cake lay like a sweet treasure. The white iced scales sparkled faintly in the lantern’s glow. For a moment, Giyuu simply stared, and you swore you could see the quiet astonishment in his eyes, soft, fleeting, but there. He closed the box gently, then turned to you, his voice even softer than usual.
“You made this.”
“Yes,” you breathed, heart fluttering. “I mean, Mitsuri-san helped, but... yes, I made it for you.”
He set the box aside with the utmost care, then faced forward, gazing out at the silent courtyard. Minutes seemed to pass in the hush of the night. Uncertain, you held your breath, not wanting to break the moment. In your mind, you worried he might scold you for fussing over him, or, worse, politely dismiss your efforts.
But instead, Giyuu closed his eyes, exhaling slowly. “Thank you,” he said.
Only two words. But they were enough to light up your entire being. A broad grin spread across your face, unstoppable, shining like the moonlight. You clapped your hands together, nearly startling him.
“Really? You’re not upset?”
“I’m not upset,” he answered, opening his eyes again to watch you. Though his expression remained mostly impassive, you caught a slight relaxation in his features, an easing of the tension that usually tightened his brow. “You didn’t have to do this. But thank you.”
Your chest felt warm and light, as though a gentle breeze had brushed away your anxieties. Encouraged by his acceptance, you slid a small knife and two wooden plates from inside your haori. “Then... would you like to try it now? The cake, I mean.”
He blinked, obviously not expecting that you would be so prepared. After a brief hesitation, he gave a short nod. “All right.”
If someone had told you earlier that you would be sharing a slice of homemade fish-shaped cake with the famously reserved Water Hashira under the moonlight, you might have fainted from the mere thought of it. Yet here you were, carefully slicing through the sponge cake, revealing its soft, sweet interior. You handed him one plate and took the other for yourself.
When Giyuu took his first bite, you watched him as intently as a hawk. His expression was, of course, hard to read, but the subtle lift of his eyebrows told you he was at least somewhat impressed by the taste. The corners of his lips didn’t exactly curve into a full-blown smile, but you caught the faintest twitch, a movement so minute, it was like the soft ripple on an otherwise placid lake’s surface. To you, it was the brightest of grins.
“It’s... good,” he finally murmured, setting the plate down on his lap.
A surge of relief and joy coursed through you, and you had to fight the urge to bounce in place. “I’m so glad! I was worried it would be too sweet or that I’d messed up the batter.”
He shook his head just once. Another few moments passed, and then he quietly asked, “Why do Westerners do this... this birthday thing?”
Chewing your own slice of cake, you took a moment to form an answer. “Mitsuri-san told me it’s to celebrate that a person came into the world. It’s a way of saying, ‘We’re glad you exist.’ It’s supposed to be a happy tradition, I think, reminding someone that their life has value.”
Giyuu’s gaze lingered on the half-eaten cake in front of him. The lantern’s orange glow caught the reflection in his deep blue eyes, reminiscent of light dancing on water. “I see,” he said finally. “It’s... nice.”
“It is,” you agreed with a gentle smile, feeling a warmth in your chest that had nothing to do with the temperature. “I think it’s important. Life can be difficult and lonely, so having a day to be reminded that others care about you... well, I think it matters.”
He went quiet again, and for a moment you feared you had overstepped. But then, you felt the hush between you shift from tension to something more comfortable, like the hush of a forest at dawn, brimming with unseen life.
You took another bite of cake, savouring the sweet taste of success. After a moment, you ventured playfully, “Well, Tomioka-san, how does it feel to have a birthday after all?”
Giyuu considered that, eyes drawn to the moon’s reflection in the small garden pond. “It feels... less bothersome than I expected.”
A half-laugh escaped you, soft but sincere. “I’ll take that as a glowing review.”
He looked at the chopsticks again, turning them in his hand as though trying to memorize every line of the carved koi. Then, in a voice so low you almost couldn’t hear it, he repeated, “Thank you.”
In that instant, the night air seemed to shimmer. There was no grand display of fireworks or musical fanfare, but the sense of closeness you felt glowed brighter than any of that could have. This was a rare moment, Giyuu opening up just enough to let you see that your efforts, though you might have been clumsy and blunt and over-the-top in your approach, had been worth it.
Your heart soared. You weren’t just his Tsuguko who needed constant correction on footwork or a stern reminder to tighten your grip on the sword. Right now, you were simply a person who cared about him, and he knew it.
A sudden rush of emotion made you talk again, perhaps to fill the soft darkness with something tangible. “I’m so happy you like it. I was worried you’d scold me for going behind your back or making such a fuss.”
He shook his head slightly, finishing off his cake slice with measured bites. “No. I understand your intentions.”
It was the longest sentence you’d gotten out of him all day. With a contented sigh, you set your own empty plate aside, folding your legs beneath you as you turned your gaze to the stars overhead. The sky felt vast and full of possibility.
Giyuu placed his plate down as well, then went back to studying the koi chopsticks. He rubbed his thumb thoughtfully over the carved shapes. In that moment, you could almost sense him trying to find words, something to convey what he felt. But eventually, he remained silent.
And you understood that silence was sometimes the best you could hope for with him, an unspoken sign that he accepted your presence, your gift, and your honest wish to celebrate him.
Quietly, you both watched the moon’s reflection on the pond, the gentle wind rustling the bare branches above. The hush felt peaceful, almost companionable, every breath of winter air a reminder that even in the coldest season, warmth could be found in shared moments.
Eventually, when the chill became too biting, you stood up, your limbs stiff from sitting still in the cold. You picked up the wooden box, careful to seal the leftover cake for him to enjoy later, and gathered the empty plates. He rose as well, his movements as fluid as ever, though he paused to ensure you hadn’t left anything behind.
Giyuu looked at you then, in the dim lantern glow, and though his expression remained gentle and subdued, there was something in his eyes that gave you courage. Maybe it was contentment, or gratitude, or a calm acceptance that came after years of drifting alone. Whatever it was, it sparked a small smile in your own eyes.
Stepping closer, you bowed your head respectfully. “Happy birthday, Tomioka-san,” you said, voice light but sincere.
He inclined his head in acknowledgment, then turned to move inside the estate. At the threshold, he paused and said, almost as an afterthought, “...Thank you. Again.”
Your cheeks warmed, but you grinned and gave a small laugh, hurrying to catch up. As you walked behind him, you couldn’t resist teasing softly, “You know, if you liked the cake that much, we can make it an annual tradition.”
He didn’t respond with words, but you spotted the faintest shift of his shoulders—perhaps an exasperated acceptance of your unstoppable enthusiasm. You took it as a hopeful sign.
By the time you reached the corridor, you felt light as air, practically bouncing on the balls of your feet. Every step reminded you that you had done something you once would have thought impossible, getting the notoriously aloof Tomioka Giyuu to partake in a Western-style birthday celebration, fish cake and all.
As you parted ways for the night, you couldn’t wipe the smile from your face. You thought of him carefully storing the chopsticks in his quarters, perhaps quietly nibbling on leftover fish-shaped cake when no one was looking. The image made your heart swell with an affection you couldn’t quite name.
In the shadows of your own room, you finally laughed out loud, hugging yourself from the burst of pure happiness. It wasn’t a typical day, but maybe that was the point. Even the quietest waters can carry unexpected warmth beneath their surface. And for the Water Hashira, on this Western-inspired birthday, perhaps a little celebration wasn’t so bad after all.