Shinobu sometimes feels like Giyu is too fitting for the title of Water Pillar. It's from the way his blade unfalteringly slices through his enemies to the way his cool, stoic gaze never wavers even in the midst of battle. He has the swiftness of a river and the calm of a lake.

But most of all, he reminds her of an ocean, vast and powerful and unfaltering—but an eerily still one. An ocean that doesn't hesitate to tear apart and drown its enemies yet remains completely still otherwise. No tides crash against its shore, no waves stir the waters, and not even ripples shake its surface.

Because it's also the way everything about him remains distant and quiet even when he's amongst his fellow Pillars. The way he always stands to the side, hand loosely resting on his sword handle as he seemingly stares at something far, far in the horizon. The way he never speaks unless he's spoken to, and even when that happens, the way the most that he ever offers are a few brusque words.

Sometimes, Shinobu wonders if Giyu's also someone who ended up locking away their true selves for a facade. If he's also desperately clinging onto a mask, wearing it to block off painful memories that threaten to break through.

But most of all, she wonders if he has ever been anything other than this unsettling stillness. If there have ever been any waves that might have once stirred this now-cold, deathly silent ocean.

~.~.~.~.~

The first hints of a ripple flicker across this ocean in a rather unexpected way.

It's during a sudden mission that Shinobu and Giyuu are both assigned to. People—including some fellow demon slayers—were rapidly disappearing in a village to the east. Their job was to investigate and eliminate the demon.

Normally, only one Pillar would be sent for something like this, but this demon was rumored to be incredibly cunning and sneaky. It would be too risky for a Pillar to get caught off-guard by themselves.

And the rumors end up being true. It takes three days of investigation for them to locate the demon. And turns out, it had been masquerading as a human for the past few weeks while eating travelers and guests in secret. It was even successful in concealing its bloodlust and hiding its demonic features to make things even more of a pain.

But like every living creature, once it's backed into a corner, its primitive survival instincts take over. Despite seeming like it relies on mind games, the amount of humans it devoured give it a fearsome strength that lets it transform from what appears to be a human into a ferocious, spitting monster.

Shinobu's breaths form faint clouds in the cold night air as she pauses to readjust her sword grip. A moment later, she darts left to avoid a furious swing of claws from the demon. It crashes into the ground below with a hiss, but then twists back on its feet to lunge at her again.

Sparks fly as a dark blue blade meets its claws. Giyu slightly grunts as he braces against the force of the demon's assault, his shoes slightly digging into the dirt.

Shinobu takes this split-second to give the demon's neck a fast, fierce jab. It recoils, a hand reaching up to clutch the wound on its neck, but not before Giyu can swing his blade in a smooth arc and slice off the arm. The demon lets out a strangled howl and scrambles backwards, its movements wild and frenzied. Its back presses against a tree trunk as blood spurts out of the stump of its arm.

The demon whimpers. "Why are you doing this to me?" The tremble in its voice, the fear on its face—it's almost human. Shinobu can understand why it's managed to deceive so many victims. "I was doing the only thing I could to survive."

Shinobu feels a twinge of what could be pity, but it's easily quelled. Anyone with a Pillar's worth of demon-slaying experience knows that this isn't an uncommon desperate final plea made by demons on the verge of death. And in a heartbeat, Giyu's already in front of it, his arms raised to prepare for the final sword swing.

"Do you really think you're different?" The demon's whimper turns into a bitter snarl. "Don't tell me that you've never had someone die for youso you could continue living on with your own pathetic life."

That's when Shinobu sees it.

For a fleeting moment, an emotion flashes across Giyu's face. For a moment, ripples shake the surface of the ever-frozen ocean. She doesn't know what it is—grief or guilt or something else entirely. But what she can see is the way the demon's words make him falter for that moment. The way he takes in a short, sharp breath and the way the tip of his blade shakes when it's usually unshakable.

At the same time, the demon lunges forward with outstretched hands in some last-ditch attempt at preventing its impending end. Its gleaming hooked claws scrape Giyu's cheek, but then right after, he brings down his sword in a powerful swing.

The demon's head flies off its shoulders and its body collapses to the ground. In a manner of seconds, all that exists of the demon is now ashes in the wind as its flesh decays into nothingness.

Giyu sheaths his sword and glances to the west. Now that their mission is over, there's no need for him and Shinobu to stick together. He's about to make his way back to the Demon Slaying Corps Headquarters when Shinobu pulls his sleeve.

He turns to face her with a slow blink.

"You're injured," Shinobu says.

Giyu reaches up to touch the wound. It's a single cut centered on his right cheek, slightly shorter than the width of his hand. "It's not serious," he says. And he's right. Normally, she would never bother with such a minor wound.

"But"—she tilts her head with a small smirk, letting a bit of her usual teasing air take over—"think about how bad of an impression you'd make if you returned to headquarters with such an ugly bleeding face."

Giyu looks slightly offended, but he doesn't protest as she reaches into her uniform and pulls out her medical kit.

Despite going through her usual routine of banter, Shinobu feels like treating his wound is for herself just as much as it is for him. That flash of vulnerability from him is just something she can't shake the sight of, and some part of her feels like treating the wound caused by it would help in some way—help with what, she doesn't know.

But of course, she doesn't say it out loud. And he doesn't say anything either as she treats him. The only word spoken for the rest of the night is short "Thanks" from Giyu when Shinobu finishes the treatment, and then they part ways.

~.~.~.~.~

Shinobu doesn't see Giyu at all for the next two weeks until they get assigned another mission together. Not that he crosses her mind much during this time. There are far more important things for her to worry about as a Pillar.

But when she does see him again, she notices how the cut on his cheek has now become a pale scar on his skin. She didn't expect such a light injury to scar, but Giyu either doesn't mind or hasn't noticed.

Their next mission requires them to cross Sagiri Mountain. It's a two-day trip, and Master Oyakata suggested they seek residence with the former Water Pillar along the way.

Urokodaki Sakonji. Shinobu has only heard rumors of him—mainly about his exceptional skills and that he was one of the greatest Demon Slayers of his time. But more importantly, she knows that he's Giyu's former teacher who taught him Water Breathing.

Shinobu herself can't think of her own past without seeing the crimson splatter of blood or the dying whisper of Kanae's last words. Despite how emotionless he seems, it's a nice thing to hear that someone from Giyu's past is still alive and well.

So that night, when they arrive at Urokodaki's home near the base of Sagiri Mountain, she doesn't expect Giyu to freeze at the sight of his former master.

"I was expecting you." Urokodaki's tengu mask gives his demeanour a permanent grimace, but his voice is warm. "Come inside."

Shinobu doesn't really know what she's expecting from Giyu when he reunites with Urokodaki, but it certainly isn't for him to simply stare without a word. She lets the silence stretch for a few more moments before she decides to break it.

"Thank you, Master Urokodaki." She smiles sweetly. "We're sorry for troubling you so late at night."

"That's no concern. Feel free to come by whenever you must pass the night." Urokodaki turns to Giyu. "Giyu. It's been a long time." His voice is still warm, but this time, Shinobu notices that it also carries hints of sadness. He places a hand on Giyu's shoulder. "Welcome back."

Shinobu sees it on Giyu's face. A ripple of emotions, the most she's ever seen from him at once. It's hard to fully tell what they are, but she can pick out small pieces. Relief. Comfort. A faint spark of happiness, even. But she can also see the other ones weaved in. Sorrow. Regret. A whisper of what could be despair.

"I'm back," Giyu says. His voice has the same flat quality it always has, but this time, there's a shake in it. Shinobu wonders if it's from happiness or something else entirely.

Urokodaki's home is rather modest and there's only one vacant room available, so Shinobu and Giyu share it. Not that she minds in the slightest. She's grateful to even have the luxury of passing the night in a shelter much safer than what she's used to in the middle of missions. She can't afford to have picky standards when it comes to accommodations.

As they prepare for bed, Shinobu says, "Did something happen?"

Giyu pauses. "What?"

"You didn't seem too happy to see your former master."

Shinobu normally isn't so prying. She knows she's being selfish. But something about the way she finally saw more ripples move across the perpetually unmoving ocean makes her needy. It makes her want to reach into the waters and see if there's a reason behind the stillness. If he has a reason, just like she does.

"I amhappy to see him," Giyu says after a few moments. "I just... get reminded of the past."

Shinobu lets out a hum. It's a short answer, but at least it's something, and right now, it's more than enough.

At dawn, Urokodaki sends them off with wishes of good luck. Before they depart, Urokodaki gives Giyu a hug. Shinobu sees it again—that flicker of emotions as Giyu freezes before letting out a small breath and relaxing, even raising his arms to lightly return the embrace.

When let go of each other, Urokodaki's left hand drifts up to Giyu's face. Giyu stiffens as his master's fingers brush the scar on his right cheek. "You have a scar here," Urokodaki murmurs.

Shinobu hears a soft, sharp inhale from Giyu, and she has to wonder how great of a significance this carries for these two.

~.~.~.~.~

To Demon Slayers, wisteria flowers are a godsend, and that's especially true for Shinobu. The fact that they're lethal to demons has allowed for the creation of her deadly poisons, and for Demon Slayers in general, demon-warding refuge spaces and barricades.

But when Shinobu gets an urgent message that an accident has caused a section of the wisteria barrier on Fujikasane Mountain to burn down, Shinobu supposes that at the end of the day, wisteria flowers are still only flowers—frail, burnable flowers. And that there are always incompetent idiots in the world who are somehow capable of accidentally causing something like that to happen.

The Demon Slayer Corps always have emergency stocks of wisteria trees that they can transport and plant, so repairing the wall isn't a problem. The problem is that nearly all the demons from the Final Selection have escaped. Fortunately, there are no populated villages nearby, but having dozens of demons running amok is certainly not a very ideal situation.

So Shinobu and Giyu get assigned to deal with the region north of the mountain. Their mission is simple: incapacitate and retrieve all the missing demons and kill them if necessary.

As night falls and they make their way to the area, they split up. It's only natural—there are only low-tier demons to hunt down so there's no need for the extra fighting coverage, and it's just much more efficient this way.

Shinobu ducks to the left as a screeching demon throws itself towards her. While it tumbles to the ground, she takes the chance to twist around and jab at its exposed neck. The violent rustling of leaves alerts her to the presence of another demon, moments before it leaps out of a bush.

She swiftly slams her sword into its sheath and twists it, feeling the click from the mechanism inside as it coats the blade with a new layer of poison. This one is something she specifically designed for this mission—a special mixture that dissolves the organs and nerves of demons enough to leave them paralyzed for a while, but not dead.

Before the new demon can reach her, she's already in front of it and gives its body three rapid stabs. It crashes into the dirt, its limbs spasming as the poison begins eating its insides. The first demon is already under the full effects of the poison, blood dripping from its eyes as it lies twitching on the ground.

Shinobu lets out a sigh as she sheaths her sword. That should be the last of them in her area, and the kakushi should soon be arriving and taking care of the rest. She begins making her way back to her and Giyu's agreed meeting spot.

It hasn't been too long since they split up, and knowing Giyu, he's probably already done with his part. Shinobu actually took measures to prevent herself from killing the demons, and as far as she knows, Giyu's plan is likely decapitate the demons and hope they don't die.

But then a muffled crash echoes in the distance, and the ground slightly trembles. Shinobu blinks. That's a bit strange. It can only be the sound of a demon and it's coming from Giyu's half of the area, but there's no way he's struggling with any of these low-tier entry-level demons. It probably managed to evade Giyu's detection. He can be a bit of an airheaded, after all.

But as she begins following the direction of the sound, the noises become clearer. The thud of something crashing against the ground. The crack of wood splintering. The squelch of flesh being sliced through. The sounds of combat.

Shinobu quickens her pace. There's no reason Giyu should be in trouble, but she wants to get there soon. Just in case, just in case there's something else going on. Something he can't handle alone.

The sounds are getting louder and clearer, and as Shinobu leaps past the last rows of trees blocking her view, the scene unfurls in front of her.

A huge, writhing mass of flesh lumbers in front of her. It's probably one of the most grotesque demons she's seen—green skin, pulsing veins, and enormous hands wrapped all around its entire fleshy mass of a body.

Giyu is facing it, sword raised and in a battle stance. He looks uninjured, which is relieving. But his haori is falling apart—it's torn at the divide in the middle, and a huge portion of the left side has been ripped off altogether. It's strange for him to have been cornered in a position where his haori would end up getting this damaged in the first place, but there's something else that's bothering her. Shinobu doesn't know if it's the way his eyes are wider or the way his grip on his sword is tighter, but there's something not right about him.

The demon's massive body shakes as it lets out a low, thick chuckle. "It's been so long, but nothing changes. All of you still end up getting eaten by me." It opens a hand, and from it, jagged pieces of cloth with Giyu's yellow-green pattern spiral to the ground.

Giyu is silent and focused when he fights. He doesn't respond to words. He doesn't fall for taunts or baits. He doesn't get angered by insults.

But right now, his breathing is hard and strangled and his hands are trembling. This isn't right. Shinobu has seen the ocean in him has stir a few times, but right now it's a storm, mercilessly shaking and crashing, and this just isn't right because there's so much emotion on his face—so much pain on his face—and out of the sheer dread that's building up inside of her, Shinobu lunges forward.

"Tomioka!" she yells.

Giyu stiffens when he sees her. He blinks and some focus returns to his eyes, but that's right when three of the demon's arms fly towards him, huge bulging fingers surround his body, and the deafening, horrible crack of too many things breaking at once fills the air.