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Lunar Cycles

Summary:

You might not expect organic lifeforms from the Earth and digital lifeforms from the moon to have a lot in common. But the echoes are there if you take the chance to listen.

Written for Cosmic Princess Kaguya! Week 2026 Day 7 (free day).

Notes:

Thank you to Lace for beta reading.

Work Text:

For Iroha, meeting Kaguya was without a doubt the best thing that had ever happened to her. She could scarcely even imagine the life she’d be leading now if her incredible partner had never joined it, and what life she could imagine wasn’t a happy one. But knowing Kaguya did leave one small eerie consequence in its wake: she could never look at the moon the same way again.

Take this particular Friday evening, for instance. Iroha, Kaguya, Roka, and Mami had just spent a good two and a half hours chatting, eating, and drinking at a fancy restaurant near the south end of Tachikawa, the three celebrities among them insisting on covering Mami’s bill. By the time the meal was through, they were all basking in the warm glow of shared quality time and mild alcoholic tipsiness – even Kaguya, thanks to some well-placed sensors in her imitation digestive system. But when at last they filed out of the restaurant into the cool, clear autumn night, Iroha found her gaze drawn upward from her friends to the silver disk of the full moon, peeking above the surrounding buildings like the eye of some leviathan creature stalking them from the void.

As Mami and then Roka met their respective taxis home, Iroha and Kaguya waited on the sidewalk to see them off – though in the lulls between, Iroha could feel that irrationally heightened sense of presence from the moon lingering unsettlingly in her mind. To begin with, just the way the Lunarians seemed to view Kaguya as theirs no matter where or how she wanted to live… the way they’d felt entitled to drag her back to work at a job she’d never asked for… and if they hadn’t known before that “Yachiyo” was the future self of the very same runaway Lunarian she’d met and briefly protected eleven years ago, then the combination of Iroha’s continued closeness with Yachiyo as performers, her telepresence robotics career, and the recent public return of Kaguya to her side had likely tipped them off. And yet…

“What’cha thinking about?” Kaguya asked, and Iroha realized she’d let her gaze rest on the moon for a couple seconds too long as the two turned to start their walk back home. Unsure whether she should be troubling Kaguya with knotted thoughts about the Lunarians, she looked back at Kaguya to probe her face – its lower half hidden under a cloth mask and her distinctive long blonde hair tied up, to reduce the chance of the two getting recognized and interrupted by fans on the street. But in Kaguya’s eyes, at least, Iroha couldn’t see anything other than genuine curiosity and a hint of concern for her worrywart partner. So Iroha took a moment to distill her thoughts sincerely into a reply.

“…I’m just happy they’re still leaving you be,” Iroha said with a soft smile.

Kaguya’s eyelids wrinkled sympathetically as Iroha spoke. “Yeah, well… they’re hardasses, but at least they’re pragmatic hardasses. They won’t go causing more trouble for themselves than it’s worth to uphold the rules. And putting me back on a leash? That’s trouble.” She gave Iroha a cocky, knowing wink.

Iroha just smiled wider for a second before the two set off toward home.


The thing about living in a high-rise apartment with huge windows on the main floor, though, was that in that space, there was no real hiding from the sky. And after Iroha and Kaguya had made it back and left their shoes and jackets in the foyer, Iroha’s gaze caught on the full moon staring at her once again as she ambled over to relax on the couch. Even apart from her anxieties around the Lunarians’ tolerance of Kaguya on Earth, Iroha had accumulated a cluster of thoughts about them that she hadn’t voiced before – but now, some combination of the alcohol and Kaguya’s openness from earlier was leading her into changing that.

“I don’t know if you feel this way,” Iroha said, leaning back pensively on the couch. “But to me, it’s weird being one of the only people on Earth who knows the answer to questions like ‘are we alone in the universe?’ Like, the holy grail of SETI is just… living with me. She’s my partner of eleven years. She’s from literally the closest celestial body to Earth. And she sings and streams and runs a mega-popular VR world, and almost no one even seriously considers the truth.”

Kaguya had been going through the kitchen cabinets, probably taking stock of the ingredients for a delivery order, when Iroha began to speak – but Iroha saw her stop and turn to listen then, leaning forward on the island counter and briefly taking on an amused smile at the way Iroha described her. “I mean, for me, I’ve known about Lunarians and humans being neighbors all along. And you know I’ve told my story to plenty of humans in the past. But nowadays, with the mass media I’m wrapped up in… if the other Lunarians don’t want proper first contact yet, I don’t want to start more beef with them by spilling everything to the public. And, y’know, human governments would get weird about me too.”

“No, no, I totally get it,” Iroha reassured. “Just… musing, is all.”

Kaguya just flashed her a small understanding smile.

“Where did the Lunarians come from, anyway?” Iroha asked. “Human astronomers don’t think the moon was ever, like, a biologically living world… but is that wrong?”

Kaguya gave an awkward laugh, replying as she stepped out from behind the counter and over to join Iroha on the couch. “Well, the truth is… we don’t know either. Our records go back… I think like 7.8 million years? But everything before that was lost in some nasty civil wars. And I don’t remember anything from my old trainings about ancient organic life on the moon.”

Iroha raised her eyebrows slightly. “So even Lunarians can have civil wars, huh?”

Kaguya shrugged from beside Iroha. “I guess so. I’ve always felt like that kind of thing could never happen on the moon these days. But I don’t know what the Lunarians of the past were like.” She smiled teasingly at Iroha and scooted up against her, wrapping her arm around her shoulders. “And don’t worry, I’m not some kind of warmonger.”

Iroha chuckled. “I know. You’re a friendly alien, like E.T.”

Kaguya’s smile turned fondly thoughtful at Iroha’s words. “That’s actually something about humans that really makes me happy, you know. Even with all the stories you tell about alien invaders… to hear the Lunarians tell it, there’s basically no such thing as a ‘friendly alien’.”

“Oh, no?” Iroha prodded.

“Oh, yeah,” Kaguya said. “Right from the oldest Lunarian stories we’ve got on record, aliens are always these terrifying bizarre creatures coming to wreck our infrastructure and kidnap our royalty and conquer the moon for themselves. And the other Lunarians take it really seriously, too – always scared of invasions from the stars like that, always wanting to be on guard. It’s such a buzzkill.”

“Kidnap your royalty?” Iroha joked. “That’s ironic.”

Kaguya’s smile remained, but it actually seemed to turn halfway sad. “Yeah, well… one of the things I’ve had to learn about humans in my time is that when they don’t try to see things from other people’s points of view, it’s really easy for them to become what they hate. Maybe humans aren’t the only ones like that.”

Iroha frowned sympathetically – not just in the abstract, but from the sense that she personally knew what Kaguya meant. Iroha had never known either of her grandparents on her mother’s side; her mother never went into much detail about what happened, but she always said they’d “abandoned” her and left her to care for her younger siblings alone while she was still a university student. In hindsight, it must’ve been part of the reason she was so determined to teach her own children strength and self-reliance. But that attitude had made the Sakayori household a living hell after Iroha’s father’s death, to the point where first Iroha’s brother and then Iroha herself moved cities to escape it before even becoming adults.

I know you didn’t want us to struggle like you and your siblings did, Iroha had sometimes felt the urge to tell her mother in recent years. But – you made us struggle anyway! You gave us so little support you practically abandoned us yourself! We both still ended up on our own too young, didn’t we?

But nowadays, her mother wasn’t the mother who berated and froze out her dependent children. She was the mother who praised and bragged about her successful adult children like their accomplishments were her own. Iroha’s brother had long wanted to let bygones be bygones, and Iroha had chosen to join him in that.

If Kaguya was the same… if the Lunarians had hurt her because of how they’d been hurt, and because of the careless, callous way they were trying to stop it from happening again… then Iroha was even happier that she and Kaguya had found each other.

“Oh, and one more thing,” Iroha said, looking at Kaguya a little concernedly. “Are you really still up on the moon right now, rushing through your work over me? The version of you from before you went back in time?”

“I mean, I must be, yeah,” Kaguya said, smiling sheepishly at the memory. “But I don’t think we should feel too bad for that Kaguya. It’ll take a while, but someday, she’ll become me.” She slid a bit lower against the back of the couch and tilted her head to rest in the crook of Iroha’s neck.

Iroha gently took hold of Kaguya’s side and pulled her closer, leaning into her. Here’s to tragic stories having happy endings.