Archive of Our Own

Adrian has never been so invested in soil sampling in their life. 

They’re crouched around a half-day from the main shuttleway, scratching a trowel through the dust and trying trying trying to focus on the sift of the sediment, the distant ring of the waychimes, honestly, they’ll even take the disharmonious cries of the skrees wheeling overhead at this point.

Behind them, Saviour of Stars Doctor Ryland Grace is in its box, consuming… nutrients. 

Adrian hums a deep noise-cancelling rumble into the dirt, soundwaves deliberately stretched beyond the limits of the alien’s hearing range. Honing in on the gullies of burrowing creatures, the footsteps divoting the path, a mineral vein just a stridelength below them, the wheels of the Rover compacting the sediment as Dr. Grace lifts a spindly hand to its face and wipes mush from around its mouth and-

Adrian cringes. 

“All done,” Dr. Grace says, tapping on its xenonite window. 

Adrian screws the cap back onto their sample collection pot, and tries very hard not to vent out a whistle of relief.  

Sat in a λ by λ cube full of flammable gas, Dr. Grace is perched-ready by the control panels of its Rover, having stashed the remains of its meal in one of the storage crates. If Adrian focuses really hard, they can pretend they don’t hear the slosh of its meal as its digestion processes commence. 

“Where are we going next?” it asks.

When Adrian replies, it’s with a careful consideration of their chords, reshaping their notes into the pidgin of Eridani grammar that Rocky still uses while Dr. Grace is learning. Language exchange is a constant battle against what frequencies its limited tympanic system can detect. 

They settle on a descriptive; “Back.” 

This particular tributary wasn’t one of their assigned sample collection sites. Adrian has witnessed firsthand what lack of nutrients does to a human body though, and diverted them to the nearest logical stopping place as soon as Dr. Grace announced that it was feeling a bit peckish. Choosing a site tucked well off the main travelpath was not incidental. Adrian may be… loosely accustomed to Dr. Grace’s eating habits, but that does not mean the rest of Erid is. Choosing a side-canyon with low risk of being stumbled upon by curious travellers was simply a matter of respect towards both parties.

Adrian must emphasise that they do not dislike Dr. Grace.

Adrian must also emphasise that this was not how they imagined their field trip going.

-

When Rocky came home after I∀λλ years around a distant sun, it felt like waking up for the first time since Adrian learned the stars were beginning to die. 

They arrived on an unfamiliar spaceship patched together like a pebble’s first sculpture project; alone aside from the fragile alien who helped save their entire planet, now laid dying behind a wall of xenonite. Adrian still shudders to imagine the number of cycles they must have slept unwatched. 

But they still came home; and Adrian’s entire world came back to life.

Erid’s focus switched from surviving to rebuilding. Adrian’s days went from modelling climate disaster after climate disaster, to monitoring the steady climb of their planet’s environment back from the brink. Where their meteorological equations were once used to count down how long Erid’s fauna had before temperature shifts rendered it extinct, they were now used to reintroduce those they had managed to save, to forecast a planet’s revival.

Adrian spent the Star-Eater catastrophe building stable microcosms to shelter Erid’s ecosphere from collapse for as long as they could.

In the aftermath, Adrian has accidentally become the lead climatologist in their Star-Saver’s biodome, taken up pottery, and tried to get to know their mate again. 

-

Because, Rocky was not the same when they returned. 

You don’t spend that long alone without pieces of you rearranging themselves to cope with the silence. The Rocky of after sleeps in unstructured cycles, is startled by loud noises and low frequencies, makes alien gestures and speaks in strange patterns that make the Elders flinch no matter how ceremoniously they hail them as Saviour-Of-Stars.

When Rocky first descended the space elevator and was swept off to the Hall of Voices, they had almost forgotten how to thrum. Their notes clumsy, like a pebble finding their collective-voice for the first time. Adrian had crushed down the urge to break something when the High Elders had the nerve to sound disturbed. 

Adrian never expected that Rocky would come back unaltered. Adrian has changed, too. Even though the Star-Eater-Eaters have populated Threeworld and 40 Eridani A grows brighter by the day, a part of Adrian is still stuck in a reality where their world is dying. Like if they let go, stop leaning their entire weight against it, the fragile biosphere they’ve crafted will entirely collapse. They know they should sleep more often than they do. 

But still, for each thing the stars have changed in Rocky, there is another that has stayed exactly the same. They’re still antisocial and jittery and debate with Adrian like they’re dancing. They still threaten divorce every time they come back home and find another clay vase in their nest-chamber. Their songs combined still feel like they could challenge gravity.

Adrian will be forever grateful that they can continue to experience love like this. If work is what it takes to keep it alive, then work is what they will do.

-

There’s also the Human.

By the airlock, Rocky is slip-sliding on the biodome’s soft silicon dioxide terrain, playing up the unsteadiness in an excuse to try and bowl Dr. Grace off its feet. The Human is laughing but also protesting in the same wheezy breath, something about its joints, how it’s going to trip flat on its face.

“Like you need my help with that!” Rocky snickers.

A few stridelengths away, Adrian packs away their hygrometer; finished checking that the biodome’s afternoon fog meets the values laid out on the human ship’s databases. They assume it’s safe to approach, given that Dr. Grace has succumbed to Rocky’s attack and now slumps gracelessly (hah) over the top of their exosuit like a lost blanket. 

“Climate observations are within acceptable parameters, Saviour Doctor Grace,” Adrian keeps their chords as simple as possible, even though clipping off the higher-pitched respect signifiers makes them want to cringe. They replace them with a dip of their carapace instead. “I will take my leave.” 

Dr. Grace mirrors Adrian’s respectful bow. “Always great to see you, Adrian,” it replies.

“You should stay for games night,” Rocky interjects, highlighting the notes with a funny little claw-flutter borrowed from another planet. 

Adrian vents an apologetic whistle, and pretends they don’t hear Rocky’s disappointment. “Not this time. Work to do.” 

As an apology, Adrian taps a claw against Rocky’s exosuit. They listen close to the return-echo as the soundwaves move through their body, all parts working-moving-singing as they should. Like a relay chain of please-be-okay, Rocky does the same to Dr. Grace. The soundwaves sink into its body and are immediately diffracted by uneven layers of soft, unprotected flesh. It sounds… jarring.

Adrian, as Dr. Grace would say, grins and bears it. 

-

“You speak to Grace like it’s your clutch-friend’s mate’s egg-parent,” Rocky accuses later, after they return from games night. “Fucking painful to listen to.” 

“It’s called respect,” Adrian prods indignantly at their scratch-tablet. “Not that you’d know what that is.” 

“Grace isn’t some stuffy High Elder. Grace walked into its own furniture ∀ times today and still can’t beat me at checkers.” 

“Politeness is still important. Besides, Saviour Grace is not my friend. Not like it is yours.” 

As they speak, Adrian is sure Rocky can hear the echo of the truth- through their nerve-fibres, the untranslatable subharmonies of their voice, the peaks and troughs of their soundwaves- that they’re not sure they want Dr. Grace to be.

Adrian does not dislike the Human. It’s impossible to hate it, when it gave up its own home to bring Rocky back to theirs. But every being has a limit to how much unfamiliar they can take. Adrian worries that Dr. Grace may cross that line for them.

Logically, Adrian knows that the Human is as close to fine now as it can be on a world it was not built to survive in. It laughs and runs on its fabricated beach and no longer sleeps for scarily long stretches of time, Rocky motionless by its bedside watching watching watching. Gravity has worn on its joints and it uses a cane on bad days, but it insists that it’s thriving. Still, every one of Adrian’s instincts tell them that anything with such an exposed, soft body should be damaged or on its way to dying. Dr. Grace saved their mate, their planet; but Adrian’s brain still crosses signals between its open flesh and the sound of carrion by the shuttleway, half-eaten with its scales pried off. It’s uncomfortable to talk to something whose speech is punctuated by the sound of fluids in its mouth, the beat of its single heart, the gentle wheeze of its lungs expanding.

Dr. Grace means the song-sky-stars to Rocky. They built a world in that spaceship, a universe for two.

If Adrian tried to get close to Dr. Grace and found themself unable to stretch the limits of their tolerance to fit it neatly inside, they could not force Rocky to make a choice between them. 

So, distance it is.

Adrian can do polite. Adrian is good at polite. They’ve dealt with stuffy Elders, years of cluster-neighbors probing whether they’ve thought about a new mate yet, ancient researchers in their field so far up the vents of their own theories that they wouldn’t notice a convection current if it flung a boulder at them. They’ve somehow ended up as the laid back one in their partnership simply by proximity to Rocky’s everything, no matter how often they were labelled an upstart in the early years of their career. 

Adrian is fine with this unconventional star system; them and Dr. Grace both circling Rocky in orbits that never have to meet.

“You’re about to have the dullest field trip known to science, I hope you realise that,” scooting aside one of Adrian’s latest sculpture projects, Rocky settles in to fidget with the tablet-stand from their reading room, the one that keeps collapsing under its own weight. The click of their claws as they work is a comforting staccato. “You’re wonderful, but even your rock samples are going to fall asleep from boredom.” 

Adrian supposes they were going to have to acknowledge the problem eventually.

Rocky has spent the better part of +V loops around 40 Eridani A avoiding their clutch-friends in every way except admitting it out loud. From the moment they returned they’ve thrown themself into work, engineering project after biodome upgrade after scientific thrum, sealing themself into a world hardly bigger than the spaceship they arrived on. So, when Rocky announced that they were finally making the journey to visit ♬♫♪♬ near the northern-plateau town they were both raised in, Adrian was so glad they could’ve sung. 

The problem: Rocky’s visit clashes with Adrian’s research trip to a collection of vent oases, the ones their climatology cluster have been monitoring since the crash in bacteria populations caused a dramatic shift in the local atmosphere. Rocky is anxious at the best of times, but the prospect of leaving both Dr. Grace and Adrian alone has them practically climbing the walls. Their star system might be an unconventional one, but stretch any orbit far enough, and its gravity will fall apart. 

Rocky cancelling their trip is not an option, not if they’re ever going to step outside and realise that the world is huge and home and waiting to welcome them. 

Adrian cannot reschedule their visit either, with the oases only accessible at specific times of the year.

The solution: Adrian is going on their research trip, and they’re going to have to take the Human with them. 

-

At least Dr. Grace seems excited by the prospect; if the way that its already too-quick heartbeat ticks up in frequency is anything to go by. It insists to Adrian that it's been fascinated by the geothermal vents since Rocky told it about them in the early days of their journey to Erid- that the chance to explore them up-close is too valuable of an opportunity to miss.

Its thoughts on the biodome team’s transport solution, however, are less enthusiastic. 

Once a fringe project in a few engineering clusters, exosuit technology has boomed since an alien who thrives in low pressure, highly oxidising gas docked onto Erid’s space elevator. There have since been thrums on adapting them for ocean exploration, high-altitude research, even some speculative collective-thoughts on the terrifying potential of future spacewalks. Using its own suit, Dr. Grace has been able to explore the research facility surrounding its biodome, give a guest lecture at the university capital, and, on one memorable occasion, hold a parents meeting for its student’s clutch-families.

Still, advanced as they are, the exosuits are not yet compatible with long-duration travel. 

So, the biodome engineers have put Dr. Grace in a box. 

With the engineering team, it refers to the tank-on-wheels as The Rover. With Rocky, it calls it something else entirely, something that makes them both teeter with laughter. 

The Rover is, for lack of a better term, clunky. With a top speed just a little over an average Eridian’s walking pace, a bulky airlock at one end so Dr. Grace can climb into its exosuit for more hands-on tasks, and little to no semblance of what it would call privacy, it’s a temporary solution at best. It takes a good few days after it’s completed for the biodome team to realise they should probably install some lights inside. As they climb inside for the final test drive, Dr. Grace’s eyebrows furrow in a way that can’t be comfortable, but it doesn’t complain. 

(It’s not ideal, but it works. Adrian could say the same about a lot of things.)

-

They take the shuttleway as far as they can; safer to stay below ground until they reach the canyon trails that lie northwest of the university capital. From there it's a steady foot-journey on paths just wide enough for the Rover to lumber down them, sheltered from the wind by sloping copper-veined walls. Despite their initial reservations, Adrian is almost glad for the Rover; finding it a useful place to stash their monitoring equipment. They could carry it themself without an issue- so long as they don’t travel quickly or experience any external temperature changes, the hot-cold mechanics of Eridian muscles do not experience fatigue in the same way a human’s flux of myosin and actin does. But the lack of bags and harnesses gives Adrian more freedom to observe the northward path, the rock-warblers burrowing in the cliffside, the pleasing chime of a tungsten vein buried deep in the rocks.

Besides; Dr. Grace insisted. It would be rude to argue.

“I can’t remember the last time I was on a field trip as anything other than a chaperone,” Dr. Grace barks out a short laugh at its own comment, muffled slightly inside its box. “I should’ve made us some bingo cards.” 

Understanding the individual words but not the sentiment behind them, Adrian settles for a neutral hum in response. Dr. Grace rubs the back of its neck. Its rate of perspiration seems to increase, and Adrian worries whether they packed enough filtered water to replace it. 

They turn northeast at the next string of waychimes. The walls in this stride of the canyon have deep striations where chatterjaws have excavated the copper, a promising sign that the native population is growing in number. Adrian is wondering whether it’s worth a quick break to take a sample for ♪♬♫♩ in the ecology cluster, when Dr. Grace lets out a startled, atonal whistle.

“It’s so blue!” It has its face squashed up against the tank, sweeping its lights over the canyon walls. “Is that azurite? Copper carbonate?” 

Adrian taps a claw against the ground, listens to the returning echo. “Copper, carbon, oxygen, yes,” they confirm. They don’t point out to Dr. Grace that they have entire caves full of the stuff back in the city. It returns a rather dull sound, so is perfect for underlaying noise-dampening pavements. 

Dr. Grace seems to want to say more, but steers the Rover onwards instead. 

The azurite veins are not the only thing it seems surprised by.

First it's the crop of mineral-spires dotted along the canyon edge- craggy tendrils fanning upwards to capture as much falling sky-plankton as possible. 

Then it’s a pair of skrees gliding above, their chevron-shaped bodies tessellated to maximise their surface area and catch the canyon updrafts.

Then it’s the wall-writing- ♪♪♪♬ and ♪♫♫♩ sang here!- left by former travellers, probably still soft in the shell with too much time to fill. 

Adrian can’t even compare Dr. Grace to a pebble leaving the nest-cave for the first time- it gets excited by the same thing twice and twice again, endlessly fascinated by uninteresting rocks and local pests. Adrian has to pause and remind themself that the human is experiencing the world in a way they cannot possibly understand. A dimension of colour and light so unfamiliar that Erid’s best linguists thrummed for days to come up with new words to describe it. 

Adrian bounces soundwaves off the canyon wall, and listens to the texture of the echo it returns. Dr. Grace looks at it and sees.

Adrian feels the limits of their familiarity approaching like a sheer drop into deep water, and takes the safe option of walking the other way. 

Amicable as they try to make them, Adrian’s one-chord responses seem to wear on Dr. Grace, and eventually it stops asking altogether.

-

Not that they would ever tell them- their ego would get too big to fit into their nest-chamber- but Adrian is starting to suspect that Rocky was right. 

They’re still at least an hour away from the first oasis, and it’s… uncomfortably awkward. 

Aside from brief visits to adjust the biodome’s climate, Adrian has never spent time alone with Dr. Grace without Rocky there to act as a buffer zone. Outside their usual template of greeting-objective-farewell, conversation hits a metaphorical stone wall less than a few sentences in.

The notes they do exchange are straight from an outdated folk-opera- all exaggerated courtesy and respect. It’s- as Rocky aptly put it- fucking painful. 

Adrian wishes Rocky was here.

(They don’t- they’re glad Rocky is exactly where they are, sparking old connections like an abandoned machine they’ve brought back to life.)

They walk on.

-

Adrian can’t help but trill a chorus of relief when the first oasis finally unfolds northeast of them. 

They drum out a radial pulse of soundwaves to take stock of the surroundings: ∀I vents in total, each many stridelengths high, scattered throughout a wide basin at the bottom of a steep escarpment. Even at a distance, Adrian can hear the muffled echo of the thick bacterial mats growing along their spires.

They waste no time in unloading their equipment, gathering samples of the rocks to check the composition of trapped atmospheric gases with their spectrometer. There’s a hiss from the edge of the basin as Dr. Grace’s airlock depressurises, and it clambers out in its exosuit. It drifts from vent to vent for a while in Adrian’s periphery, then finally ambles over towards them. 

“What are you measuring?” it asks. Even through the flat monotonic syllables of its language, Adrian can hear curiosity. 

“Checking mineral deposits for any trapped byproducts of vent bacteria metabolism,” Adrian explains, tapping a claw against the textured display of their spectrometer. “I sulfur, V hydrogen.”

“Hydrogen sulfide!” Dr. Grace drums an excited rhythm into the dirt- a strangely Eridian gesture. “Same as the deep ocean vents on Earth.” 

 “Earth vents have similar atmospheric conditions?”

Dr. Grace’s head bobs enthusiastically. A nod. “Light doesn’t reach the deep oceans- like on Erid. Primary production down there uses hydrogen sulfide gas from hydrothermal vents instead, bacteria then take the chemical energy to fix carbon for food.” 

It speaks quickly, but Adrian can just about parse the meaning. “Interesting interesting interesting,” they sing a layered melody in reply. “On Erid, hydrogen sulfide is a byproduct, not a fuel source. Nitrogen from ammonia is used for chemical energy. The remaining hydrogen reacts with sulfur in the rocks.” 

“Different chemistry, same outcome!” Dr. Grace claps their hands together, punctuated by the clink of xenonite. “Convergent evolution. Some of my old colleagues would have a field day with this. I wonder if…” 

Dr. Grace slips into thought, so Adrian takes the opportunity to switch instruments to their thermometer, measuring the air temperature above the vents. By the time they move onto recording the pressure gradients formed as the superheated air rises, Dr. Grace has returned, following them closely as they scratch down datapoints onto their tablet. To pass the time, they piecemeal together an explanation of how Adrian’s instrumentation works. Half of it is based on approximations and context cues- Dr. Grace is not a meteorologist, and Adrian is not yet entirely fluent in the flat tones of its language- but they manage to make it work. It’s surprisingly easy to talk to, when science is the topic at hand.

The back and forth is almost… enjoyable. 

The Eridian scientific process is normally a straight-to-the-point ordeal. If you want to share your findings, you thrum about it. A few minutes is all it takes to communicate your entire life’s research; it’s direct, efficient, and Adrian (alongside most scientists under +ℓIℓℓ years old) kind of hates it. Sometimes, it's nice to spend time explaining your work. To lead someone from hypothesis to conclusion without skipping past the years of trial-error-failure-success that waymarked the journey. To discuss the ongoing questions and watch the answer evolve in real time, rather than needing to arrive with a polished final symphony. 

Adrian supposes that’s why so many of their colleagues love talking with Dr. Grace. It’s impossible to thrum with someone whose brain runs on a chaotic network of electrical impulses and chemical gradients. There’s no chance of establishing a connected resonance when each thought ricochets stop-start, a delay of ∀λV nanoseconds between each synapse.

By the time Adrian is finished with their observations, they understand the geological diversity of Earth’s hydrothermal vents, and have a loose idea that human meteorological devices aren’t all that different to Eridian ones. (“Convergent evolution again,” Dr. Grace has a habit of laughing at its own jokes. “Who’s gonna tell Earth and Erid that they arrived to the party wearing the same dress?”)

Adrian has to stumble towards each answer, and for once a conclusion feels like a journey to share, not just a statement to make.   

-

Eventually, it’s time to move on. Adrian packs their equipment back on top of the Rover, and they head due east, towards the next oasis. Dr. Grace claims it needs to stretch its legs and sets the Rover to roll autonomously behind them both, wandering ahead of Adrian in its exosuit. It seems happy to forego conversation in favour of scanning its light over the mineral veins in the canyon wall- now resonating something zinc-based when Adrian taps a searching echo against the surface. As they walk, Adrian focuses on fitting their rough data against the theoretical trajectory they calculated for the vent microclimate’s recovery. They’re plotting the atmospheric sulfur content, when the air is split by a startled shout northwest of them. 

Dr. Grace has wandered a few stridelengths ahead, towards where the canyon levels out into a shallow scoop. In the opening, a pack of rock-warblers are feeding on a downed skree, their defensive cries raising a disorienting chorus as they round on the sudden intruder. Dr. Grace has its hands up placatingly, just standing there as one of the warblers snaps forwards. Only then does the Human hop backwards, almost stumbling over a rock as it goes and- 

Adrian can almost hear the phantom crack of its fragile body against the hard ground. It might be tougher than the rest of it, but hydroxyapatite is not a durable material to build a skeleton from. Adrian does not like to call what they feel panic, but all they can think is that it would break Rocky even more than they’ve already been broken if something happened to Dr. Grace while they weren’t around to prevent it. It’s this knowledge that kicks them into motion, bounding towards the Human and scooping it clean off the ground. The rock-warbler crashes ineffectively against Adrian’s leg, and the pack scurries back to their burrows, leaving the skree half-gutted in the dust. 

At such close quarters, Adrian can feel the slosh of fluid through Dr. Grace’s circulatory system. It floods towards its face more than usual, and Adrian hopes in all five of their hearts that it's not a sign of some otherwise hidden injury. 

“You can put me down,” Dr. Grace’s voice is strained at the edges, so Adrian deposits it gentle-as-possible by the shelter of the Rover. It immediately drops to the ground cross-legged, clearly intent on testing the limits of the exosuit’s flexibility. “Please tell me you’re not going to make a habit of tossing me around like a hacky-sack.” 

“Only if you say you won’t run off again, Saviour Grace.” 

“Run off-” Dr. Grace hisses a sharp breath through its teeth. It’s not a sound Adrian has heard it make before; something harsh and frustrated. “You don’t have to treat me like some sort of… of soft-shell!” 

Adrian startles at that. Hearing a human approximation of a crass Eridani idiom is unexpected. Hearing it from this Human- who avoids cursing in its own language like it’s a plague- even more so. (Adrian can guess exactly where it learned it from.) They almost comment on it, then think better. 

Shoulders sloped forwards, Adrian starts to recognise the shape of Dr. Grace’s posture as humiliated.  

“I get the concern- squishy space blob, I know,” it continues. “But I’m an adult. If I do dumb stuff, then that’s my own problem. I take full responsibility for getting bitten by a giant Eridian pillbug if that’s what it comes to.” 

Dr. Grace goes to run a hand frustratedly through the soft fibres growing from its head, and meets the dull clunk of xenonite instead. It smacks its fist into the dust as a substitute, and Adrian tucks their legs close to their carapace guiltily. It’s one thing to remain aware that someone was not built for the same environment as you. It’s another thing entirely to swaddle it like a pebble in soft sand. Maybe their lines got a bit crossed, somewhere along the way. 

(Because Adrian knows this frustration. Has experienced it themself- back when their star was dimming and their mate had disappeared to save it and their cluster-neighbors and clutch-family kept offering to split their work and clean their home and bring them food like they’d suddenly become incapable of existing in a world without Rocky in it. Handling them like crystal until they’d wanted to scream.)

They may have messed things up, just a little.

“I believe you are capable of doing dumb stuff and fixing it, Doctor Grace,” Adrian bows low, hoping it carries the apology from sound to vision. “I would appreciate it if you didn’t get predated before we’ve even reached the next oasis, though.” 

At the very least, that gets a short laugh out of Dr. Grace. “Noted.” 

Then its face scrunches up- a frown. “It would help if you stopped full-name-and-titleing me though. Jeez. I feel like I’m about to be told my grades are disappointing.” 

Adrian tilts their carapace, confused. “It’s respectful.” 

“It’s uncomfortable,” Dr. Grace corrects. “I’m going for friendly coworkers, not disciplinary hearing in progress.” 

“Doctor Grace-”

“Please,” there’s an odd note to the human’s voice. “Just Grace is fine. It’ll help a lot.” 

Adrian pauses. Then, against their better judgement-

“Grace.”

Grace’s mouth tugs at the corners, showing its teeth. Smile.

Adrian taps a claw against the ground to listen closer.

-

They stop again not long after so Grace can begin its sleep cycle. 

The canyon has flattened out into a shallow scoop, so it parks the Rover in the shelter of a windcarved arch and clambers back into the airlock. It’s brought a stack of blankets from the biodome with it, and wastes no time in constructing a haphazard nest with them in the corner of the tank.

“Reminds me of camping,” it says nonsensically, before settling down to sleep.

Adrian barely watches for more than V hours before Grace is up again, shimmying closer to the barrier. “Wanna play Uno?”  it asks, brandishing a stack of textured xenonite cards. 

Adrian is pretty certain that humans are meant to sleep for longer than that. Grace waves the cards again. 

“I don’t know how to play,” Adrian admits. Apparently, that’s as close to an agreement as Grace needs.  

“Bet you’ll pick it up faster than Rocky did,” it grins, and makes for the airlock.

-

Unfortunately, beating Grace at Uno is incredibly satisfying.

-

When Grace admits defeat- both to the need for sleep and its inability to stop Adrian from pulling reverse cards on it- Adrian settles back in to watch. 

It’s not the first time Adrian has watched the human sleep, but it still catches them off-guard every time it rolls or sighs or gets its blankets tangled around its limbs, constantly moving even when unconscious. 

They wonder if Rocky felt the same unease when they first stood sentry to Grace’s sleep cycles, jolting instinctively every time it made its strange asleep-awake noises. Or, if they were just glad to steal a slither of normality back from everything empty space took from them. 

Adrian knows that they will never be able to fully comprehend what Rocky went through, up there. The only being who could come within solar systems of understanding is asleep in front of them now; there will always be a Star-Eater-Trail of belonging connecting the Saviours of Suns, no matter where they go in the universe. 

Though, to say they were written in the stars would be to imply they didn’t have to fight hand-and-claw for it. Adrian isn’t sure if there’s a word in either of their languages to encompass what they mean to each other.

By contrast, there are almost too many words to describe what Rocky means to Adrian. 

Home; for one. The layered tune of their waychime, composed from the jewelry they both wore when they pledged their songs in the Cave of Voices. The grumbling noise Rocky makes when they realise that Adrian has rearranged their furniture again. The symphony of their first debate, when Rocky told them they have garbage opinions on the best way to mix xenonite polymers just minutes after they met, and Adrian’s entire world exploded into sound.  

Here’s what Rocky means to Adrian. Here’s what Grace means to Rocky. What Adrian means to Grace-

Humans call it a three-body problem.

And some problems just don’t have a solution.

-

Once Grace has woken, downed a nutrient shake and gone through the disturbing process of brushing its teeth, they set off again.

The path eventually leads them into the tangle of a vast mineral-spire forest- the polyp colonies leaching zinc and copper from the rocks to construct intricate tendrils that ring pleasantly in the steady wind. Grace is out of its box again, fringing the path to study the structures closer. It’s taped one of its lights to the top of its exosuit for a more hands-on experience, and keeps hobbling back to the Rover to stash branch-shards in the airlock, likely to study later.

It starts humming not long after. 

The sound isn’t exactly pleasant, but as Grace said before; it’s a grown adult. Adrian is in no position to tell it what it can and cannot enjoy- even if what it enjoys is singing wet, off-key melodies.

Mid-refrain, Grace glances over its shoulder and falls sheepishly silent.

Adrian sighs. The awkwardness is back. 

“You studied alien life when you were a scientist on Earth?” They ask, the question painfully abrupt in the ambient forest-noise. Adrian’s turn to cringe. “Just making conversation.” 

To its credit, Grace doesn’t comment on the clumsy opener. It slows its pace to fall back in beside Adrian “Not at first. I started closer to home with extremophiles- species on Earth that live in environments nothing else can survive in.” 

“My thesis was on hypolithic cyanobacteria- kinda like the photosynthetic organisms in your upper atmosphere, except they live in some of the driest places on Earth. They grow underneath translucent rocks to stop UV light from the sun literally frying them.”

It kicks awkwardly at a rock as it walks, frowning when it gets stuck unsatisfyingly in the dirt. “My more… radical theories came later.” 

“I understand. Learning many many many facts about few few few things allows for…” Adrian pauses, searching for the right phrasing. “... Some imagination to develop.”

That gets a laugh out of Grace- a proper one, the full-chest thing Adrian often hears when the human is with Rocky. It’s strangely gratifying. “Good to know that PhD trauma transcends solar systems. At least your imagination didn’t get you excommunicated from your field.”

Unable to hold back an amused chitter at the memory, Adrian dips their carapace in a facsimile of one of Grace’s eyerolls. “Don’t be so sure. I was removed from my first research thrum for unconventional use of convection models. Annoyed many Elders in the climatology cluster.” 

“No way,” Grace leans in closer. “You never struck me as a rebel, Adrian!” 

Adrian huffs. “It’s not rebellious if I was right,” they hum proudly then, stand a little taller. “The Adrian formula helped accurately predict atmospheric changes caused by 40 Eridani’s dimming. Unconventional convection models gave Erid more time to prepare.” 

(The calculations Adrian developed during the Star-Eater catastrophe are still some of their best work- even if that work did leave them with a full-time career in expecting the worst, and ultimately stopped them from following Rocky to the stars. They both had missions to complete.)

Grace spends a few beats processing their words, then makes a strange noise.

“Ohh jeez,” it sounds a little strangled. “You have an equation named after you. You’re a scientist scientist,” it turns towards Adrian, its glasses crooked on its face. 

“You and Rocky are what my kids would call a power couple. Hope you know that.” 

Adrian whistles flatly. “I understood less than half of those words.”

Bearing its teeth in a grin, Grace knocks its elbow into Adrian’s carapace- xenonite against chrysocolla- and continues walking. 

-

The next collection spot is not as dramatic as the last. Rather than a city of vents in the scoop of a deep ore-rich basin, site V is a scattered collection of young seeps bubbling up from the mantle, towers barely taller than Adrian themself. The only defining feature of the site is the brine pool sat in the middle, scattering sound unpleasantly across its surface and making distances difficult to judge. The high salt content is the only thing stopping Adrian from warning Grace not to fall in. It would probably just float. 

“Fewer samples to collect here,” Adrian announces, making for their equipment bags. “Won’t take long.” 

Grace doesn’t reply. 

It’s wandered right to the edge of the brine pool- so close that Adrian wonders if the water is causing issues with its own feeble hearing too- and its light is angled somewhere in the distance. Adrian is about to repeat themself a little louder, when Grace finally speaks; more breath than words. 

“Adrian, it’s so beautiful.” 

And- it’s not often an Eridian wonders if they’ve heard wrong.

Because it’s just a pool. Some walls. No interesting mineral veins, no exciting rockforms, not even enough wind to make the surface vents chime. It’s- for lack of a better song- boring. 

Adrian flutes out a high, confused note, and tells Grace as much. “It’s just water. Nothing special.”

It’s very clearly the wrong thing to say. Grace deflates inward, crossing its arms in front of its ribs like it's got something to defend. “If you could see the colours-”

“I can’t, though,” their tone hits a sharper key than intended, and Adrian flinches. “Apologies. I did not mean to offend.” 

“It’s fine,” with an absent shake of its head, Grace just turns back to the pool. “Completely different sensory systems. Of course we’re gonna have different ideas about what’s beautiful.”

When put like that, it sounds… incredibly lonely. 

(Grace stares out over the flat plane of the water. Adrian wonders- not for the first time- what it must be like to exist in the version of Erid only it calls home.)

-

When Grace eventually wanders back over, Adrian is busy setting up their anemometer, scratching down their wind speed observations as it settles into an uncomfortable looking criss-cross on the ground beside them. Adrian hears its joints pop. 

“I have a confession,” it says, serious as anything. Adrian immediately braces for the worst. 

“I genuinely have no clue who it is that Rocky’s gone to visit.” 

Adrian’s laugh of relief whistles right on the edge of the human’s hearing range. “That’s all?” 

“Don’t laugh- this is serious! We never got that far into our Eridani lessons, and now I’ve been here too long for me to ask without making it weird. I need to learn, but I want some of my dignity to remain intact- so asking Rocky is off the cards.”

Adrian is starting to see what Rocky means when they call the human dramatic.

 “How long do you have? Global Common Eridani has over IIIV relationship motifs. We will be here a while.” 

Grace audibly slumps. Again. Dramatic. “And there I was thinking your tonal harmonics were bad.” 

Still, it sets itself back upright. “Eridani immersion hour. Rocky and I did this on the Hail Mary while we travelled. It’s only fair that our roadtrip has language lessons too.” 

Adrian trills another laugh. The linguistics cluster had some… choice notes about Rocky’s language curriculum when Grace first arrived. They settle down, one arm still tuning the anemometer. “Which of our collection would you like to start with?” 

“Simple terms for my tiny human brain please. Start who Rocky is visiting.” 

“Easy terms only,” Adrian promises. “Rocky is visiting ♬♫♪♬. Their clutch-friend; an Eridian who was raised in the same nest-chamber. Can share egg-parents, but don’t have to.”

“Right, pebbles are raised communally. Would’ve been nice to know about the whole ‘it takes a village’ attitude before I chose a tiny room for parents' evening…” 

Adrian is learning when it's best to let Grace just murmur to itself, and when to step in before it disappears into a tangent. They continue. “You have many clutch-friends as a pebble, fewer as an adult. Only keep the ones who mean most to you.”

(Keep the ones who mean most, and hold them tight. Alongside Adrian, ♬♫♪♬ was one of the only Eridians who continued to believe with all five of their hearts that Rocky would return home. They waited waited waited, through dimming stars and everyone’s lost faith, and Adrian hopes that ♬♫♪♬ can finally stop being patient and start being happy.) 

“Got it. We have childhood friends in English, but that… doesn’t really cover it,” Grace smiles lopsidedly, before Adrian can say anything. “Inefficient language, I know.” 

“Didn’t say anything,” Adrian hums, teasing undercurrent bell-clear. 

Next, Grace asks about Adrian and the rest of the university climatology department (cluster-neighbors- people you work with. Neutral form, but can be decorated with subtones to make it as agreeable or disagreeable as required). Then about itself and the biodome team (exchange-partners- a mutually beneficial trade of knowledge between two parties, a palindromic series of notes for a two-way system). And then-

“What about you and Rocky?” It asks.

Adrian hesitates. Grace had asked for easy terms only; how can Adrian distill the entire universe of song-debate-dance-home that they and Rocky have built into a string of simple three-octave chords? 

“Life-partners,” they settle on, a little helplessly. “Everything.”

Then, finally- 

Grace doesn’t ask. Adrian can tell it wants to know. 

“You and Rocky are ♬♪♬,” Adrian flutes out the notes with care. They weave together like a story; a fated meeting, inevitable and unavoidable but still overlaid with the tone for amazement, a harmonic to tell the world that something unexpected happened here. It’s not a song sung lightly. 

Grace’s breath hitches wetly in its lungs. When it eventually replies, it does so unsteadily. “We do have a word for that one. Soulmates, I think.” 

“Not entirely inefficient, then.” 

Grace just sniffs quietly in response. 

They both know Adrian can hear it. They both pretend they can’t.

-

“You’re full of surprises, Adrian. I didn’t think you’d be into the whole…” Grace says, once it's gone through the whole rigmarole of de-suiting and depressurising just to wipe its eyes dry in the airlock. It waves a hand, like Adrian will be able to detect the words through the disturbance of the air. “Fate thing. Scientists usually aren’t.”

“They should be,” Adrian rebukes, tweaking the gain on their particle analyzer with one claw. “Fate is scientific. It’s just chance in a different key.” 

Grace sits a little straighter, a universal gesture of tell-me-more. “C’mon. You can’t just drop that on me and not elaborate. It’s the philosophy part of the roadtrip.”

Adrian sighs, but is quietly happy to oblige.

“A boulder slips from a cliff-face, but narrowly avoids the settlement below,” they tilt their carapace in Grace’s direction, the way they’ve heard Rocky do time and time again to show where their focus lies. “You say it’s fate. You could accept that as a spiritual event and be done with it. Or you could accept it as probability, and realise that you can change it. You can build the settlement away from the cliff face. You can build platforms to catch the boulder before it falls. When you see it as chance, nothing is predetermined.”

(This, always this, is what kept Adrian going through lonely days and dimming stars and hopeless stretches where it felt as if they were carrying an entire planet on their back. Nothing, not even fate, is unchangeable. It’s not something they speak about often, yet they find themself singing it all for the Human to hear.) 

 “It’s the same when a Human and an Eridian converge on Tau Ceti, and somehow arrive in the same lifetime. Both chance. Both fate. Neither set in stone. You worked for it, and made the extraordinary option happen.” 

They focus back in on their particle analyser, while Grace seems to sit with what they’ve said, turning it over through the electric-threads of its mind. 

“I like the way you think, Adrian,” it replies, eventually.

They whistle; sharp and amused and annoyingly pleased. “Flatterer.”

-

“You and I are ♪♫♪,” Adrian says later, before they can lose their nerve.

Grace looks up from where it’s trying to figure out the sample loading drawer on Adrian’s spectrometer, and replies with an eloquent; “huh?” 

“Ask Rocky about it later.” 

Extending the telescopic arm of their thermometer, Adrian lets Grace’s protests blur into background noise.

-

(♪♫♪. A song for two soundwaves, sung in parallel. If undisturbed, they will never interact. If guided, skewed by the tiniest realignment, they will inevitably collide.

Whether they cancel out or amplify; maybe that’s all up to fate.)

-

Grace is restless. 

It’s not subtle about it, looping the perimeter of its box as the Rover inches its way back into the gully of another canyon. It's got both a laptop and a tablet propped up against the control panel, as well as some sort of writing-board balanced tucked under its arm which it scribbles on at sporadic intervals.

Fidgeting might look different on a human than on an Eridian, but Adrian can’t keep themself from finding the motions familiar anyway. 

A constant, mindhumming restlessness is something Adrian has always been accused of; theirs and Rocky’s home is a constant symphony of claw clicks, absent humming, piles of abandoned hobbies and half-finished projects. In the years after Rocky left, Adrian almost forgot how to sit still entirely.

Grace reaches to type something on the laptop, knocks the tablet onto its foot, and hurls its pen at the Rover’s wall in quick succession.

“Would you like to play Uno again?” Adrian stomps to get its attention.

(A distraction. That’s what Adrian would need.)

Grace considers the offer, then shakes its head. “Best to keep moving. Maybe you can show me an Eridian roadtrip game instead? We can swap.” 

With a thoughtful rumble, Adrian shimmies in a rough approximation of a human shrug. “We have games, but none for travelling,” they splay their claws apologetically. “Also most take a long long long time to play. Rocky will come looking for us and find we have started to calcify.” 

At least that makes Grace chuckle. “Are all Eridian games like this?” 

“All the ones worth playing.”

It asks if Adrian likes complicated games. When they trill an affirmative, it grins widely.

“Do I have a game for you, then. Remind me to teach you about D&D when we get back to the biodome.” 

(Suddenly, Adrian and the Human have future plans. Isn’t that something.)

They end up teaching Grace a repetition game for young pebbles, something simple it can whistle along to easily. The notes are designed to get faster and trickier to slide between with each round, but thanks to its completely alien anatomy, Grace is surprisingly proficient at it. 

Adrian hums, pleased. Maybe they’ll get a harmony out of it yet.

-

They reach site λ not long after the end of Grace’s next sleep-cycle. 

It’s another basin field, the largest of their collection- with vents so tall they’d be indistinguishable from the rockforms around if it wasn’t for the deep rumble at their hearts. It isn’t often that Adrian feels towered-over, but here they definitely feel their sense of scale being flipped as they probe the surroundings with a searching echo. 

As soon as they spot them, Adrian leads Grace to the drumhorns clustered up the side of the nearest spire, guiding it to press a xenonite-shielded hand into their fronds and feel the body-deep pulse of their song. It laughs as the vibration travels up its arm, and Adrian hears tiny muscles pulling the hairs on its limb to stand on end. 

“I can’t hear it, but-” it shakes out its hand, then presses right back in again.

“Their sound is too low even for Eridian auricles,” Adrian explains, leaning their own carapace close to feel the inaudible thrum. “But the vibration proves it’s still real, even if we cannot hear it.” 

Still, they draw the line when Grace goes to stick its entire arm into the cluster. “Your limb will go numb. Stop.” 

It doesn’t even have the decency to act sheepish about it.

This time Grace insists on helping Adrian set up their equipment. It’s just about wrapped its brain around the workings of an Eridian thermometer- (“We use mercury for these on Earth. So glad you don’t use haemoglobin for yours.”)- so it busies itself taking temperature readings while Adrian grinds up rock samples for their spectrometer. 

Adrian still can’t quite overcome just how strange the Human is, but it’s still fascinating to observe Grace as it works. 

It’s noisy, unprotected, fragile but still for some reason insistent on refusing to sleep and clambering on top of its home to watch the fabricated stars projected on its fabricated sky. It refuses to call itself brave, but it gave up its entire planet to save someone else’s. Its lifespan is shorter than some university courses, but it refuses to dedicate that short existence to a single thing; intent on learning everything, everywhere, all at the same time. 

The Human is contradictory, unsettling, and Adrian is kind of starting to see the appeal. 

They’re not proud to admit that- when Grace arrived halfway dead with Rocky refusing to leave its side for longer than a heartbeat- they assumed the Human was simply the only thing around to watch a lonely Eridian sleep. A bond formed out of necessity. 

Adrian knows now that it’s so much more than that.

Because Grace is smart, a good teacher, painfully genuine below its occasional wall of bad jokes and know-it-all comments. Always listening-looking-observing, even when it seems oblivious to the world around it. As it potters around the circumference of the vent field, scratch-tablet wedged under one arm and Adrian’s thermometer extended above its head like a weatherpole, there’s something almost familiar about its sound. About the way it taps the ground as it walks, feeling it out in a way that’s distinctly Eridian. All the idioms and gestures it’s borrowed from its now-home; so strange coming from its tall, soft body, but comforting all the same.

As Adrian has come to understand; it wasn’t just Rocky who returned from the stars changed. 

Something in them both broke up there, and like the spaceship they arrived on, they patched together the wreckage with pieces of each other. Their waychime reflects it: an Eridian song meant for Human ears. 

Adrian couldn’t be there for Rocky while they were away in the stars.

But someone was. To Adrian, that means the entire world.

(And- that’s the root of it all, isn’t it? The separation, the arms-length, keeping Grace as no more than a curiosity to observe from a respectable distance. If they hurt this unfamiliar, remarkable visitor from another planet, they would be hurting part of Rocky too.)

“Adrian!” By the Rover, Grace has the thermometer slung over its shoulder, one foot propped on the airlock. “Think I’d get a better reading if you gave me a boost up there?” 

Adrian doesn’t want to hurt Grace. It doesn’t help that the Human seems to want to do it for them. 

They shake their carapace disbelievingly- their own borrowed gesture- and pretend they didn’t hear a thing.

-

As is often the case, conversation eventually circles back to Rocky.

They took a short detour down a quiet sidepath so Adrian could eat in privacy and review their notes, plotting the observations they’ve collected. Grace has settled beside them in its exosuit as they work, its chatter forming a not-unpleasant ambient noise.

“It was ridiculous,” a recount of the biodome team’s latest effort at producing socks segued into a tangent on storage solutions segued into an old grievance from ∀+ years sealed in a metal tube. “He could hear the layout of the entire ship- he knew there were only five rooms to work with- and what does he do? Brings every one of his worldly possessions on board, that’s what.” 

Adrian chitters good-humouredly. While many things about Grace are incomprehensible, this they understand all too well. “And then- let me guess- they took offence to all your own belongings? My pottery is grounds for legal action, but the Vλ boxes of xenonite polymer in our living chamber are fine.” 

“Hah! Hypocrite- that’s what we call it on Earth. One day I’m gonna make a passive-aggressive storage container for his socks, see how he likes it.”

“They deserve it for having terrible taste in interior design. Let me know the dimensions. I will help.” 

That gets another full-body laugh out of Grace. 

“Jeez, I would die for that rock, but his attitude-” 

It stops talking, abruptly. 

Adrian pauses their derivatives with a confused whistle.

“Sorry,” Grace turns away. “Maybe a bit much.” 

Somehow, the explanation just confuses Adrian more. They lower their scratch-tablet. “You are always like this with Rocky, though. I’ve heard. Many times.” 

“Yeah, but-” it sighs an unfamiliar sound, frustrated but a step to the left. “Human thing, I guess.” 

(“Human thing,” Rocky once told Adrian, on the fringe of the biodome as their fabricated waves rolled in to greet the shore. “Bullshit. Real translation: I’m too scared to just fucking talk.”)

-

Adrian is good at polite. 

That doesn’t mean it always works, though.

-

“I’m not concerned that you’re trying to ‘steal’ Rocky from me,” Adrian tells the human, as soon as it leaves the airlock after its next sleep cycle. “Or whatever else it is you’re convinced is happening here.” 

Grace replies by choking on its own spit. 

The sound rattles Adrian right down to their claws, but they push on. “If you make jokes about Rocky in the biodome, then you can make jokes about Rocky here. If being apart feels like a limb being pulled off, then you feel like your limb is being pulled off here too. My presence does not change this.”

When the Human just stares at them, Adrian whistles frustratedly. “Clarification: Rocky is important to you. Rocky is also important to me. These statements do not cancel out.” 

“No I-” at least that seems to get Grace speaking again. “I know that. I just-” 

It splays its hands, a five-pronged version of an Eridian apology. “I need you to understand, Adrian; the thought of going home to you was what kept Rocky going though some of the worst days we had in that tin can. He told me so much about you, so many wonderful things, and I got all in my head about how I had to get you to like me, or I’d be letting him down.” 

“I do like you,” Adrian replies, half-instinct. The respect harmonic is laid on so thick it almost gets stuck on the way out of their vents. 

Grace returns a disbelieving hum. 

“I do not dislike you,” they correct. 

They both know there’s more to it than that. 

With a sigh, Adrian skims a claw over the silicate indent of their mate-band; tracing the piece of not-them-but-also-them that they promised their heartsong to. What Grace and Rocky have built is different, less conventional- soft skin burned and scarified- but it sings the same story. Someone so important that they’ve become a part of you. The similarity, stretched across solar systems, gives Adrian courage.

 “I was not jealous,” they confess. “I was scared.”

Adrian never thought the Human could sound so still. 

“You mean so much to Rocky. You spoke about how they came home for me, but not how they would willingly delay that so you could go home too. You learned to live with each other’s strangeness- even if you do disagree on the definition of music, or the correct place to store foot-coverings,” Adrian pulls their focus from the quiet heartbeat of the world around them, and lets it all settle on Grace. “You’re unfamiliar to me, though. Disgusting in some ways, fascinating in others. Most things about you, I don’t understand at all. Apologies for any offence caused.” 

“None taken,” Grace says weakly.

“I would rather deal with distant formalities than risk getting to know you, and finding that you’re too different for us to ever get along,” Adrian speaks slowly, carefully- because they want to be sincere, not because they doubt that Grace will understand. “I like to learn. I am a scientist. But that does not make me brave.” 

“Oh, gosh,” and Grace leans back, the sound caught in its throat some halfway-point between a laugh and a sob. “Adrian. You have no idea how long I’ve been feeling the same.”

-

“The pool from before,” Grace notes later. It’s fashioned itself a seat for the Rover out of some tape and a used carbon dioxide scrubber, and is still committed to the art of sitting on it incorrectly. “It was the same colour as you.” 

Not long ago, there was a trend on Erid of having Saviour Grace tell you what colour you are. Something about it dictating personality, compatibility, and songs know what else. Adrian never saw the appeal. Still, they hum curiously. “The wavelengths matched?”

Grace nods, punctuated with a small yep. “We call it turquoise. Similar to some oceans on Earth.” 

It’s an interesting revelation: the Human looks at them, in a dimension Adrian cannot understand, and sees an ocean. 

“Your circulating cells stretch and compress soundwaves as they move. Forms currents. Similar to some oceans on Erid.” 

(Adrian listens back, and hears an ocean too.) 

-

While they may have plenty of experience with it, Adrian never claimed that patience comes naturally to them. If they don’t hear something other than feldspar in the next I+ minutes, they’re going to do something drastic. 

Grace seems to agree. It has found a way to get its makeshift chair to spin, and is doing so with reckless abandon. 

Adrian reminds themself that they are incredibly lucky. They are collecting measurements to document the revival of their planet, mapping the answer to predictions they designed using models they developed. They are doing science that they love, in a field that respects them. They could not ask for more. 

“I spy with-” Grace starts. “Hmmm nope.” 

If they don’t hit the final sampling site soon, Adrian worries they might both go a little bit insane.

-

The deep chime of history rings through the valley. 

Even Grace seems to notice that the waychimes strung from rock to rock are more ornate than usual, shimmying closer to the windows of its box to take a look. Adrian plucks a claw against one of the markers as they pass, parsing the specifics of its song. An idea has crystallised before the final note has even rung.

“Has Rocky taught you anything about Eridian theology?” Adrian asks Grace, then actually thinks for a second. “No, of course Rocky has not taught you about Eridian theology.” 

“Hey, I know some stuff,” Grace protests. “You guys have a lot of religions, right?” 

“Many, many, many,” Adrian trills an affirmative. “Almost more than we have relationship motifs. It would take your human brain a lifetime to memorise them all.”

Grace winces at that.

“But there are similarities; most agree that we came from the ground. It is a common belief that the first Eridians were given their voices in Singing Caves like this one,” They strum at the waychime again, filling the air with sound. “They are very important places to Eridian culture, no matter what you believe in. Would you like to visit it with me, Grace?” 

(Underneath the question, Adrian plays a second song: welcome, familiarity, here is a piece of my home, I’ll share it with you.)

Grace only hesitates for a moment, before it nods so enthusiastically its vertebrae creak. “I’d be honored.”

The well-trodden pilgrimage-path is only permissive to the Rover for a little while longer, so they park it below an alcove and Grace clambers into its exosuit to make the rest of the journey on foot. They’re both hesitant to leave the Rover and its life support machinery behind- Adrian almost talks themself out of the whole endeavor- but curiosity wins in the end, and Grace stumbles out of the airlock in record timing. Its palms seem uncomfortably damp. Adrian hopes it’s from anticipation rather than fear.

The path winds them slowly below ground, waychimes punctuating each step of the journey. Deep veins of quartz catch each tap of Adrian’s claws and stretch their soundwaves into something beautiful. This particular Singing Cave is grander than the one near the university capital; neither Adrian nor Grace need to duck as the waychime trail ends to let the cave speak its own story. 

They pass through the antechamber, Adrian reminding Grace gently to mind its step as it almost goes stumbling over a cairn constructed by previous travellers. North of them the space yawns open, wind sweeps through and-

Every corner of Adrian’s being is flooded with music. 

Adrian does not often consider themself spiritual; they know the physics of how the quartz crystals diffract and scatter the wind’s soundwaves into a song, a thrum, an entire story. That doesn’t stop them from feeling anything but wonder as they trill a quiet melody and the Singing Cave turns it into a symphony. The music brings them back to themself, a temporary shedding of all the loss and grief that has calcified around them in the years since that first thrum in the Hall of Voices told the world our star is dying. 

Beside them, the Human is silent. Then-

“I can’t hear anything.”

And, of course. 

Adrian knows the limits of the human auditory system inside and out- has spent the better part of +V years shaping their vocabulary to fit inside it. The Singing Cave’s voice falls far outside of that range. Stood there in its exosuit, all Grace must be experiencing is still, silent darkness. 

Adrian doesn’t expect the thought to feel so crushing. 

(It’s just another reminder that, no matter how hard they try, there are some differences that Adrian will never be able to overcome.) 

With a gentle clunk of xenonite on quartz that rings an inaudible chorus through the amphitheater, Grace sits and motions for Adrian to do the same. 

“Can you describe the sound to me?” it asks.

Its own reminder. 

There are things that Grace will never get to experience. There are things that Adrian will never be able to understand. But with patience, with curiosity, with eyes and auricles open- maybe they can learn what it would be like to.

-

(And somewhere; fate shifts, probabilities are recalculated, and a pair of parallel lines begin to converge.)

-

“Remind me again how the diffraction step works?” Grace leans closer to the particle analyzer, checking the texture-screen against something it has written on its own tablet. 

They’re hiding out in a sidechamber of the northern-plateau engineering cluster, running through samples Adrian collected at site λ while Rocky and ♬♫♪♬’s collective-voice forms a pleasant background hum. Adrian reaches past Grace to adjust one of the dials. “High frequency soundwaves enter the sample here. Any particles present cause disruption. The pattern is used to calculate an attenuation spectrum, differs depending on particle size.” 

Grace nods seriously, jotting down another note.

“Adrian. My true-song. My heart's chorus,” Rocky drops themself between Adrian and Grace in an undignified sprawl. “You’ve infected it with fluid dynamics. Stop.” 

Adrian clinks their limbs together in hello, then trills an amused arpeggio. “Don’t be jealous. It’s not my fault I’m more interesting than you.”

Rocky vents an outraged whistle at that, drumming their claws in an indignant staccato. While they’re steaming, Grace pats the top of their carapace soothingly. 

Rocky hisses an atonal traitor at it, but still leans into the contact. 

They remain there a while longer; a strange pile of alien limbs, an unconventional star system. Adrian recapping how to interpret the tactile waveforms on the analyser readout, Rocky pretending to be singlemindedly invested in repairing the frayed strap of the satchel Adrian is wearing, Grace wriggling its legs between both of their bodies like they’re its personal space-heaters. 

Rocky flicks on a small solder-stick to anneal the satchel fastenings back together, then announces that they’ll be sleeping soon.

Adrian taps a claw once-twice against Grace’s exosuit.

(They don’t need a shared language to agree that they’ll wait and watch together.)