Eirin can smell Kaguya before she sees her. It's a horrible, unclean, familiar smell—the stink of blood layered with the sharp, acrid tone of ashes. The princess settles to the floor behind her with an inelegant thump. Eirin doesn't even bother to look up from her writing. By now, she already knows what she'll see. "Welcome back."
Kaguya doesn't answer. She never does, on occasions like this.
Eirin finishes her writing and turns in her chair. She isn't surprised at what she sees: Kaguya is injured, maybe even near death. Her clothes are soaked in blood, apart from the holes that show gashes in her flesh beneath. Her robe is brittle and blackened across one shoulder, and the holes show skin blistered from burns beneath. There's a ring of bruises around her neck, a scrape across her face ending at her now-crooked nose, and one arm hangs at her side, probably broken.
It's happened so often that what comes next is practically a ritual. Eirin shakes her head softly. "Let's get you cleaned up."
After easing Kaguya into a tub, Eirin fetches a bucket of water and a wash cloth, then gently removes the princess' ruined clothes. Naked, she looks almost worse, in some ways: the perfect porcelain skin that made her a prize for hundreds of suitors is still there, but it's marred with clotting blood, bruises, welts, the shattered tip of a rib jutting from her side. Eirin ladles up some of the water and lightly pours it across the princess' back, washing away blood and dirt to reveal the puckered wounds beneath.
It's slow work, but neither of them are in any rush. Eirin knows that Kaguya isn't in danger; with the slightest push from her powers, she could remind her body of its eternal nature, restoring it to peak health in a second. But sometimes, Eirin suspects, she just needs to linger like this, to feel pain and the nearness of death, to be suffused with the impure nature of this broken world she's chosen to live in.
And sometimes, Eirin knows, she needs to care for Kaguya like this. In some ways, she still feels too much a part of the moon, too separate from Earth to possibly understand why Kaguya's face shines so brightly when her hands are around Mokou's throat. It's the one thing that Eirin knows she'll never be able to give her. But if she can be there afterward, to help ease her recovery and remind her of the gentle princess she is at heart, she's resolved to do what she can.
Kaguya lifts her good hand without prompting, and Eirin cups it in her own. It's as much a mess as the rest of her, one fingernail torn off at the root and raw flesh stuck beneath the others. Eirin rinses them, revealing the jagged tips, then gently lifts her broken hand and does the same.
It leaves Kaguya mostly clean, although still battered. Eirin stands to fetch her surgical bag, but before she can leave, Kaguya says, "Wait."
"Hm?"
The princess tilts her head back to look through the window. Outside, the moon is just barely visible peeking through the clouds. She's silent for several seconds, seeming to be weighing a heavy decision. "I left her alive," she says softly.
Eirin inclines her head in understanding. "... very well. I'll deal with her first."
This isn't such a regular part of the ritual. It only happens a few times a decade, but after a century of such decades, it's become routine enough. Eirin slides her bow from its place on the wall and grabs a single arrow. It's a point of pride that one is all she'll ever need.
The walk into the Bamboo Forest of the Lost is long, but Eirin doesn't mind. It's strangely peaceful out here tonight. The light of the moon gleams off pure snow, and no sounds except Eirin's own footsteps break the silence. Other times that she's done this, she's had to hunt, searching for her wounded prey in dark and tangled kilometers of bamboo, but tonight, she can just follow Kaguya's footprints.
She knows she's getting close when drops of blood appear between Kaguya's tracks, and soon enough, she crests a small ridge and can see the recent battlefield below her.
They've learned to have these fights without burning down the forest, but that doesn't mean they aren't destructive. A small depression between two hills reveals ground mostly bare of snow, turned into a muddy mess, and the bamboo in a ten meter circle is all scorched, broken, or outright destroyed. In the very middle of the circle: Mokou.
The girl is laying on her back, and it leaves Eirin with an unpleasant display. Her shirt is torn to rags, and beneath it, her skin shows long raw marks where Kaguya had clawed her. Unlike Kaguya's wounds, Mokou's all look like they were inflicted by hand. Even the gaping hole in her abdomen.
And yet, as Eirin watches, Mokou's chest very slowly rises as she takes a wheezing breath. She's unconscious, at least. That always makes this less unpleasant.
Eirin shrugs the bow off her shoulder, then nocks and draws an arrow. Both are works of art. The bow, a wonder of Lunarian craftsmanship, far more powerful and light than any of its human counterparts. It was presented to her as a ceremonial symbol of her wisdom and leadership.
The arrows, Kaguya crafts in her abundant free time. Each one is a unique masterpiece, covered in delicate filigree and displaying craftsmanship that a mere human lifetime could never achieve. She spends hours making each one, carving scenes from her memories along their shafts. Each one will be used once, and only for this purpose.
It's the closest Kaguya will ever come to writing a love letter.
Eirin carefully aims, then releases the arrow. It flies soundlessly. The razor-sharp tip breaks Mokou's ribcage with the slightest crunch and pierces cleanly through the girl's heart.
A barely-perceptible shudder runs through Mokou's body, and the last of her blood spills to the ground. It sizzles. Her body crackles, and in a matter of seconds, erupts in a white-hot blast of heat. Eirin averts her eyes, but she knows that if she were to look, she'd see feathered wings of flame.
In a pyre of her own body, Fujiwara no Mokou burns to ashes and is reborn.
Dying is always a strange experience for Mokou. Her body feels too... fresh afterward. It's tender and unmarked, lacking all the little cuts and callouses that accumulate in daily living. She can feel every brush of her clothing—also new, since her earlier outfit burned along with everything else—as she lights her kiseru with a flick of her fingertip.
Even the smoke feels unexpectedly harsh in her virgin lungs, but she's gone through this hundreds of times. She holds the breath, savoring the burn in her chest, and only slowly releases it through her nose. "She was laughing."
Eirin raises one eyebrow. "Excuse me?" Mokou isn't sure why the Lunarian feels the need to escort her home after these incidents, and yet, there she is, standing in front of the steps to her shack.
"Your princess. She was laughing the whole time. Just ripping me open and laughing." Mokou takes another slow drag and looks up at Eirin expectantly.
"I thought you moon people were supposed to be better than us," Mokou says, when Eirin doesn't respond.
There's a longer silence this time. "Couldn't even finish me off herself, could she?" Her eyes meet Eirin's, trying to prompt some response from her, and the physician holds her gaze.
"Does that bother you?"
With a sigh, Mokou lowers the pipe from her mouth and gives it a practiced flick with her finger, sending a few spent ashes to land at Eirin's feet. "It doesn't bother me, it just seems like she could finish the job if she likes it so much."
"I see."
"So, what's your percentage in it?"
"To what do you refer?"
"In killing me. You could just leave me there. I would've gotten over it sooner or later."
Eirin crosses her arms and looks at Mokou critically. "I'm a sworn physician. It would be against my creed to let you suffer for so long. And I feel a certain... obligation to you. My Hourai Elixir is the cause of all of this in the first place."
Mokou grunts. "If you're expecting me to sob about how much it sucks being immortal, you can forget it. I got over that a long time ago."
"Did you?" Eirin's voice is so level, Mokou's first instinct is to tackle her here and now. See if she's so smug when there's a hand around her throat. She'd take no joy in it, though. Even assuming she could win, she's had enough pointless violence for one lifetime.
Some fights, though, are anything but pointless.
Eirin leaves, after about the fourth time that Mokou reassures her that she's fine. Once she's barely out of sight, Mokou rises to her feet, fetches a jug from inside her shack, and follows after her. The path from Eientei to the spot where the pair fought is well-trodden now. She stays just far enough behind to keep herself hidden.
When Eientei comes into view, Mokou circles around. Here, especially, she knows the terrain well enough that she could navigate it with her eyes closed. Her outfit isn't going to blend in very well in the snow-covered bamboo, so she goes for a spot where she knows she's mostly concealed by the underbrush, then sits down on a boulder without bothering to brush the snow off, pops the cork out of her jug, and takes a deep sip of homebrewed booze.
Across the clearing, she can see the back of Eientei. Kaguya has the doors slid open, and is sitting on the edge with her feet dangling. She, too, looks entirely recovered from her ordeal, in a fresh pair of clothes. Mokou can see her raise her hand in greeting to Eirin, and the pair have a brief conversation before Eirin steps into the house.
Alone again, Kaguya raises her eyes and looks out into the darkness. Mokou takes another sip from her jug. Already, she can feel the slight floating in her head that tells her that the alcohol's hit her bloodstream. It's not much of a surprise... her newly-minted body will need a few months to build up a tolerance again, and the fact that her stomach is empty probably doesn't help.
Kaguya's scanning eyes lock onto hers, across dozens of meters, and linger for a second. There's a definite edge of recognition there—no way Kaguya didn't spot her—but she turns away and her eyes look up toward the heavens. They both sit there, and...
And what? This isn't the first time she's done this, and she still doesn't know why she keeps coming back. It's a little thrill, though, the feeling of sitting within shouting distance of Kaguya and just... drinking. Being a person. Looking up at the same stars she's looking at. Being aware of each other and yet at peace. It's a nice reminder that, even though their hands were dripping each other's blood barely two hours ago, they're not animals.
Ten minutes into the visit, Mokou's head is already swimming. Is she really this much of a lightweight when her liver's fresh? Usually-silent parts of her brain whisper to her, no longer kept in check by her inhibitions. She could run across the field. Barely fifteen seconds and she'd there. Close enough to kill Kaguya, or break her neck and spend long minutes watching her die, or talk to her or kiss her or fuck her or whatever it is she wants from this visit. Hell if she even knows. Right now, all of the above sound pretty nice.
From the inside of the manor Eirin steps out, carrying a tray of drinks, and Mokou's resolve dissipates. Whatever she comes here for, it doesn't need to involve the rest of Eientei. Mokou's not much of a philosopher, but she's had a lot of time to think, and she's read plenty of stuff about the nature of infinity. It doesn't sit well with her common sense, but the way the books describe it, anything compared to infinity is nothing. Smaller than nothing, even. She could kill Kaguya a hundred thousand times, kiss her a hundred thousand times, have a hundred thousand conversations, break a hundred thousand bones, a hundred thousand nights under the moon drunk and hands tugging at each other's clothes, and in the end, it would only be the tiniest insignificant speck compared to the eternity they're going to spend together.
Maybe she'll eventually do all of them, and more. She's got a lot of time to kill. But for now, Mokou takes one last swig, plugs her bottle, and turns to head for home.
Kaguya takes a steaming cup of tea from Eirin with a grateful nod, but her eyes don't move away from Mokou's retreating form until it vanishes into the underbrush. Even at this distance, the sight brings back memories from earlier in the evening. The feeling of flesh tearing under her fingers, little fibers of it snagging under her nails. The snap of a bone breaking in her own hand as she slams it into Mokou's face. Blood, warm and thick, running down her arm to drip from her elbow.
She's killed before, in a desperate fight to avoid getting dragged back to the moon, but that was different. What she does with Mokou isn't about necessity. It's about emotion, and freedom. On the moon, her every action carried great significance, chains of symbolism and tradition that dictated her every step. When she's fighting, there's no certainty and no boundaries.
It's exhilarating.
It's the most alive she's ever been.
It's the most connected she's ever felt to another human being.
When the feud started, ages ago, it was Mokou attacking her for the whole... situation with her father. For centuries afterward, she fought back, attacking the one who'd tried to kill her out of some sense of justice or self-defense. But for a long time now, the vendetta has been little but an excuse. Who cares about some millennium-old slight? Kaguya only wants the rush of euphoria and the sense of closeness she feels when she and Mokou have put their lives in each other's hands.
Eirin silently settles into position behind her and starts combing her hair. Kaguya lifts her cup and takes a sip. The tea has chilled a little in the winter air, but it's still warm. It instantly brings back another memory: She bites into Mokou in a fit of passion. Warm, thick blood runs into her mouth and down her chin. She pulls back, coughing but delighted at her own taboo act, and giggles drunkenly as she plants a bloody kiss on Mokou's cheek...
Some day, she supposes, she'll get bored of it. Nobody understands infinity better than Kaguya does, and she might be the only person alive who can really comprehend just how long it is. There will come a day when it will grow stale. But there's no rush. For now, she's content to bask in it, to explore every nuanced variation of anger, pain, fear, and hate.
She will squeeze every bit of rage from her heart, savor it like fine wine, and when it's exhausted, there will still be an eternity left ahead of them.