Chapter Text
Rocky was extremely creative. Ever since the first encounter with the xenonite sculptures he’d made of Grace’s ship, he knew Rocky was also probably smarter than him by a mile. Most of the time he was smart enough to put the pieces together, especially with the Eridian’s chopped up english from the translator being no help, but it didn’t get better when he could understand Eridian language.
Even so, Eridian customs were extremely new to him. He’d spent most of the time in space doing important “saving the stars” related things, so his time on any kind of Eridian research was limited to whatever Rocky and Adrian had told him.
It had been at least a few months since him and Rocky landed in Erid, and days started going by like it was all scheduled. Wake up, see Rocky and Adrian, teach the Eridians, eat something (mostly me-burgers), and go home to sleep.
On the other hand, Rocky and Adrian were his mates, and it was the best thing ever to be so close with them both. Their relationship was mostly muddled down to caring for each other when needed, one of them sometimes spending the night in Grace’s biodome, and the occasional gift made by mostly Rocky. But Rocky’s scheming had reached a whole nother level.
——————
Grace’s day started as normal, but he didn’t wake up to his alarm this time. He sat up in confusion, rubbing his eyes to adjust to the morning light shining through the window. Clink, clink, clink. It was a consistent noise coming from the side of the room, and only did he notice it was Rocky when he put on his glasses and pushed them up his nose. He honestly couldn’t tell if it was a pile of clothes at first and the sound was a delusion, but then said “pile of clothes” skittered around to grab another tool for his mystery creation and he knew immediately he was right.
Rocky was tinkering away at something shiny, given the reflection of light from outside refracting off whatever it was onto the wall like glitter. To be honest, Grace couldn’t make out anything else at all, his curiosity driving him to swing his legs off the bed and get up, walking over to Rocky. “Hey, Rock. What’cha got there?”
Rocky jumped a bit, even though his hearing is way better than a human. His self awareness is slightly off.
“Rocky make gift. Gift for Grace,” He hummed, finishing up the xenonite chain attached to whatever it was. He then happily put down his tools and picked up the object, holding it up to Grace. “Is jewelry! With special Eridian jewels! Make Grace more more pretty.”
Grace’s face lit up, smiling and taking the fragile necklace from Rocky’s hands. There was an array of small gemstones, a big teal gem in the middle with engravings in the middle of it. It sparkled when Grace moved it back and forth in front of his bidome’s window.
“Thank you, Rocky! I have so many gifts, I don’t know where I should put this..” Grace scanned around the room, but his eyes snapped back to Rocky when he made a loud melodic chirp to grab his attention.
“Grace should wear. Took long long time. Not easy to make. Make Grace look more beautiful!” If Rocky had a face, he’d be beaming up at him.
Grace laughed, his face a bit hot from the praise, and he took a moment to consider. Grace didn’t usually wear jewelry aside from a few rings, but he also never thought he could like anything romantically until he and Rocky got closer. Ultimately, he decided it was a good idea. He liked seeing Rocky happy.
“Yeah, okay. I’ll wear it,” Grace flattered as he unhooked the clasp, bringing it around his neck gently and snapping the clasp back into place. It was surprisingly light, the large gem in the middle the heaviest component of it.
Rocky was continuously humming with excitement as soon as Grace said he would wear it. “Yes! Grace wear! Good good good!” His enthusiasm made Grace chuckle, patting Rocky’s head (or top of his carapace) through his form-fitted xenonite suit. “Grace very good for Rocky. Make Rocky happy. Pretty pretty Grace.”
His praise made Grace swoon, turning his head to the side and hiding his blushing face from Rocky. Obviously, it was useless since Rocky could hear his heart skip a beat. When he turned, his eyes averted Rocky, and he looked at the clock for a split second, realizing he might be late to class if he didn’t start getting ready. He sighed, kissing the top of Rocky’s carapace quickly before flashing him one more smile. “You guys spoil me too much. You’re lucky I don’t mind it.”
“Grace deserves it! Is great mate,” Rocky hummed as Grace walked away, still smiling, stretching and patting Armando on the arm to remind him to grab his clothes.
——————
Class that day started as usual, no problems at all, and Grace taught like he usually would on these mornings. His new necklace shown proudly on his chest, resting on his neck with a slight shimmer from the gemstones.
After his first lesson, he took a 5 minute break from teaching to eat something, which he’d forgotten before because of Rocky’s surprise. He sat down on a stool next to his desk, eating a me-burger he had taken with him, when he heard the first few snickers and whispers from the Eridians.
At first, it seemed like regular Eridian gossip, of which was very normal to him, but he noticed there were a few words that didn’t sound like the normal gossip he’d hear from his students. Words like “mate”, “claim”, and “Dr. Grace” were being tossed around. He stopped chewing when he heard “mate mark” come out of one of the Eridians. Never before did they talk about mating or mates in class, and nobody knew Rocky and Adrian were his mates except for him. He’d never talk about his personal life in class.
He gulped when he heard “blue” from one of his students, choking down the food in his mouth and staring down at the necklace. He watched it rise and fall as he breathed, looking back up before said student noticed he was staring. Something was different about that gemstone, especially the markings on it.
He initially brushed it off, as maybe some sort of coincidence, but when his students continued to gossip throughout class and barely pay attention to their topic, Grace knew it was something to do with that necklace. His Eridian students were usually always on task and never really got distracted, but the one day he changes things up, his class is completely distracted.
If only Adrian were home, they’d back Grace up. Adrian was off at an science - centric panel presenting the group’s findings on human behavior and biology, including other stuff like Astrophage and Taumoeba project progression. He kind of wished he were there, but Adrian was persistent on going alone. Gosh darnit.
Rocky’s in for one hell of a talk.
——————
Once Grace had finished up with work and lesson planning for the next day, he walked back to his biodome and peered through the window. Rocky was using the laptop with Armando’s help, just researching more things mindlessly. He didn’t really have much to do, since Adrian was the one who did most of the research on Erid for the important stuff.
Grace slowly pushed the door open, walking in and shutting it behind him. Rocky, of course, looked straight at the door as soon as it closed and chimed happily when he saw Grace. “Hi Grace! Eridians good today, question?” He rushed over, skittering across the floor.
“Not bad. But something was off today.” Grace sighed, taking his cardigan off and throwing it down on a chair nearby. He looked back at Rocky, putting his hands on his hips and raising an eyebrow. “You suppose you know what that is?”
“Rocky no understand. Why Eridians no good, question?”
This darn rock was acting like he didn't know what he was talking about, meanwhile the large gem on the necklace shimmered in the light.
“Listen, I’m just gonna tell it as it is. Is there something I don’t know about this necklace, Rock?” His eyes stayed on Rocky, watching as he tilted his carapace in confusion.
“Grace not know, question?”
“Don't know what?” Grace’s heart rate sped up slightly, one of his hands moving off his hip to take a closer look at the large gem in the middle. The engravings were painted with gold so they were more bold, shining brighter than the gem itself. They were definitely purposeful marks, no doubt.
“Rocky and Adrian mate mark on gem. Is show you are Rocky and Adrian’s. No one else.”
Grace’s heart skipped a beat, and his whole body froze. He almost forgot to breathe as his body heated up. He regretted how he didn’t ask what they were initially, covering his face with his hands in embarrassment. He has their mating marks on his lower abdomen, near his thigh, and he didn’t bother to check for resemblance.
“Rocky! You should have told me! Now my whole class knows I’m mated. Jesus criminy.. “ Grace ruffled his hair with his hand, his other hand behind his neck. His face was noticeably flushed.
“Is good! Now all know Grace is owned. Grace not available. Only Rocky and Adrian’s.” Rocky chirped, patting Grace’s marks through his clothes. It’s kind of embarrassing how turned on he is right now.
Rocky’s right. No other Eridian would want a leaky space blob like him. They only see him for his looks, which admittedly are something Eridians praise him for. But it doesn’t feel the same as when Rocky and Adrian call him pretty. It directly hits his heartstrings every time.
“But Rocky- Oh my god Im an idiot,” He whispered the last part, very flustered, walking over to his bed and sitting on the edge of it. “Did Adrian know about this?”
“Yes. Gave Rocky the gemstone for carving. Adrian said good good idea. Make Grace more pretty and beautiful they said!” Of course they did. Grace completely forgot how much they enjoyed scheming together to surprise him. His mating marks throbbed erratically as he shifted slightly.
Rocky came over and stood in front of Grace, his claw moving and then resting on Grace’s thigh. Grace shuttered at the touch, hiding his face from Rocky, still embarrassed. “Yes, it's beautiful, Rock, but.. geez..” He huffed, turning his face back to Rocky and pushing his glasses up.
“Rocky want other Eridian to know Grace not taking more mate. Grace only for Rocky and Adrian. Only us touch Grace’s body and hear his mating calls.”
Rocky moved his claw, holding Grace’s waist gently. “Yes.,” He whispered, not being able to stop
himself as his clit throbbed against his boxers. The thought alone of being owned really messed with him, especially thinking about having Rocky and Adrian’s clutch once they figured out how to mold their ovipositors to the xenonite.
“Take off clothes,” Rocky ordered. Of course Rocky noticed Grace’s hips canting upwards slightly and his heart rate speeding up. They’ve been doing stuff like this for some time, so it’s no coincidence how Rocky just knew what got Grace going.
Grace obliged, taking his shirt off slowly and then pushing his pants and boxers off simultaneously. He reached up to take off the necklace, but stopped when Rocky practically growled at him. “Leave on jewelry." Christmas eve..
“Do I have to?” Grace whined, putting his hands on the bed. It wasn’t any more exposing than the permanent mark on his lower abdomen, but he was already embarrassed enough.
“Yes. Or Rocky no touch Grace.” His direct tone made Grace throb with anticipation.
Since he was already so worked up, but most likely unable to get himself off because of how accustomed he’d become to Rocky’s hands, he huffed, nodding his head. “Okay. The necklace stays on.”
“Amaze! Good, good Grace,” Rocky charmed, using enough force not to hurt Grace but to push Grace back further on the bed, making him squeak at the sudden movement.
Rocky swung two of his legs in between Grace’s legs, sitting on his left thigh somewhat as he got more comfortable. He brushed over the markings on Grace’s lower abdomen again, making Grace shutter. His pussy was already throbbing and slick, his chest rising and falling sporadically as he breathed irregularly, the necklace shimmering seemingly brighter.
Grace really did like the necklace. He wanted other Eridians to know he was owned. No other Eridian could make him squeal and moan like Rocky and Adrian did, or treat him with the gentleness and tenderness Rocky and Adrian did during the day. It would be a dream to hold their clutch and have their eggs. Fudge, he was in so deep that he’d do anything for that.
Grace was shaken out of thought when Rocky moved his hand and grazed his throbbing dick, moving his thumb up to it to rub it in small, painfully slow circles. He shivered, grasping the sheets under him. “Rocky..”
His whimper made Rocky trill happily. “Beautiful Grace.. Rocky should make more jewelry for Grace. Grace would love.”
“Mh.. Yes— They’re beautiful!—“ His voice trembled as Rocky’s speed increased, his glasses moving askew on his face, blurring his vision slightly.
“Grace very good. Good good Grace. Very beautiful mate for Rocky and Adrian.” He spoke in a slightly different melody, making Grace feel all the more better.
“Yes! Ohh- FFUDGE!” Grace practically screamed, Rocky swiftly moving his hand and pushing two fingers into Grace’s leaking cunt.
“Grace would look very very pretty, so cute and stupid with Rocky’s touch and jewelry. Would look even better with Rocky and Adrian’s clutch.”
Grace’s heart practically thumped out of his chest, biting down onto his own knuckle briefly to hold back an embarrassingly loud scream, groaning low as Rocky’s words penetrated his brain, making him buck his hips. It’s like the gem on his necklace was an aphrodisiac, because he was so pathetic and horny that it was like never before. Not even as bad as he’d had it when he got his permanent marks.
His speed was still way too slow for Grace’s liking, making him whine. He was always slow to begin with, mostly to get more out of Grace. It always worked. “Rock, faster, please ..” He was almost breathless, but Rocky didn’t let up.
“Grace need beg for it. Then Rocky go faster.” He was seriously pushing his limits. Grace knew if he had a mouth, he’d be smirking.
Grace happily obliged, being he had no smarts left to fight Rocky about it. “Rocky.. Please, please give me more. I need you so bad it hurts. Fudge— I want you to claim me. Claim me over and over again I-I’ll happily let you. Mark me more, anything. Rockyy.. “ He rolled his hips on Rocky’s fingers, eagerly waiting for his decision.
“Will Grace wear all jewelry Rocky and Adrian make for Grace, question?” His voice was a low hum, his arm practically vibrating as he spoke.
“Yes— Anything. Please,” Grace whimpered, running his hand over his markings. “Make me yours..”
Rocky made a sound Grace had only heard once or twice, but it was low and grainy, sounding somewhat of a growl, and his fingers pulled out slowly. Grace whined pathetically at the loss, but Rocky wasn’t done.
“Rock..” Grace muttered, panting and drooling. His glasses were hanging by a thread, his vision blurred. He held onto one of Rocky’s arms as tightly as he could, practically giving him puppy dog eyes.
“Stupid, stupid Grace. Rocky make Grace so pretty, so dumb, so leaky.”
Without warning, Rocky plunged his fingers back into Grace’s tight pussy, but this time his entire fist was inside of him. Grace couldn’t hold back the scream this time, his back arching off the bed.
“Good good Grace. Rocky know you can take it.”
“F-Fudge, Yes! Yes, yes - AH!” Grace writhed and moaned, Rocky’s spare arms being the only thing holding him down. He got louder, letting Rocky know he’d found the sweet spot.
Rocky’s fist felt so deep, it made Grace’s brain leak out of his ears to make room. His speed was punishing, not too fast but hard. Rocky had taken notes on the few times they’d done this on how different rhythms and force made Grace feel, and he could tell. His memory was impeccable.
“Rock— Oh my god- “ Grace panted, drool dripping down from the corner of his mouth and his hand resting on top of his markings. His body felt electric, spasming slightly with sensitivity as he felt the coil in his stomach tighten.
“Im- Uhng— “ He couldn’t even get the words out, but Rocky knew he was close.
“Grace so so beautiful. Finish for Rocky.”
Grace could barely hold back his curse this time. No matter if he even tried to censor himself. “FUCK — “
After a few more thrusts of his fists, Grace let his orgasm rip through him with Rocky’s name on his lips. His vision blurred, whining and moaning with pure white, hot pleasure as Rocky let him ride it out.
Once Grace’s legs began to shake from overstimulation, Rocky stopped his movement and slowly pulled out his fist, wiping it down on the bedsheets. They’d clean that up in a bit. “Good good good Grace. Very leaky, very good,” He vibrated, chirping happily as Grace panted, swinging his forearm over his eyes.
He moved his hand up and wiped the drool off of Grace’s chin, moving his glasses up his face more so Grace could put them back on correctly. He grabbed them from Rocky, moving his arm and putting them back on, pushing them against the bridge of his nose. Looking at his thighs, Grace saw Rocky clearly again and smiled.
“That was— Wow. Geez.” His voice was somewhat hoarse, and it made him cringe.
“Grace like necklace, question?” He knocked his fist against the bed twice for a question, like he used to do in the Hail Mary a lot.
“I think so, Rock. I think so.” He laughed, reaching out for Rocky. He quickly skittered across the bed, nestling between Grace’s arm and his chest, curling his back arms underneath him like a house cat. Grace rested his head on Rocky’s carapace, holding the necklace in his free hand.
“Adrian come back next day, question?” Rocky shifted slightly, as if looking up at Grace.
“Yeah. I know, I miss them too. I think you’re gonna have to make more of these.” He laughed, shaking the necklace slightly. Rocky giggled as well, nodding his carapace as if to say “yes” (of which he picked up from watching Grace). They lay in silence for a bit, just existing in each other's space after their intimacy.
“I like the gem color. It reminds me of us.” He whispered, slowly letting his eyes close.
“Rocky and Adrian never leave Grace. Always love Grace.” His voice was softer, like he was talking in a whisper. Grace smiled brighter. holding the gem tighter in his hand.
“I love you both too.”