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Grian’s stopped paying attention to the porn playing on Mumbo’s laptop in favor of kissing up his boyfriend‘s neck when Mumbo chokes on his tongue and slams the laptop’s lid shut. When Grian pulls away from the dark mark he’s been working on just above Mumbo’s collarbone—good luck hiding that one under a shirt collar—Mumbo runs his fingers over it and groans.
“Grian.”
“Sorry,” Grian mumbles, not sorry, already scouting out his next spot below Mumbo’s ear. “It’s fine, nobody’ll notice.”
“Doc will notice. And he’ll make jokes he thinks are subtle but aren’t,” Mumbo shivers. “And he’ll try to do the secret handshake thing.”
“Oh, the horror,” Grian deadpans, inching his right hand closer to Mumbo’s laptop.
“You know how much I hate the handshake thing.”
“It’s not that hard, you know,” Grian points out, dragging the laptop over from Mumbo’s legs to his own. No point in being subtle, frankly, Mumbo’s too wrapped up in his monologue to even notice.
“It’s not, though, I never know what comes after the weird fist-bump part.”
“Not a bear hug, at least,” Grian says, mostly to distract Mumbo while he opens up the laptop. Unfortunately, the video starts playing again once he’s in and a particularly obvious slurping sound drags Mumbo’s attention back to Grian.
“Yes, thank you so much for reminding me, that was one time—what are you doing?”
“Figuring out what made you freak out,” Grian answers, scanning the scene in front of him. No real use in subterfuge at this point.
“I did not freak—wait, how do you know my password?”
Grian doesn’t dignify that with a response. He turns the laptop around to Mumbo instead, and Mumbo makes that weird face again and averts his eyes, blushing. Interesting.
“What’s wrong? Did someone fart or something?”
“Ew, what? No.”
“Then what is it?” Grian shoves the laptop towards the foot of the bed, glancing back to make sure it’s not in danger of falling before he crawls back into Mumbo’s lap and wraps his arms around his shoulders and the back of his neck. “Not into—“ he glances back towards the screen, “—tramp stamps? Bleaching?”
“No, I—well. It’s. It’s a bit unsanitary, isn’t it?”
Grian rolls his eyes from the safety of Mumbo’s neck. “It’s porn. They probably, you know, douche and everything.” He can’t help but shift a little bit on Mumbo’s lap, shiver as Mumbo’s chest hair rubs against his nipples. “What, did you try it with someone and get grossed out?”
“What? No, I haven’t ever—“
Mumbo trails off. Intriguing. Grian pulls away from his second hickey till he can see Mumbo’s face again. “Really? Never?”
“No,” Mumbo says, face scrunching up like he’s smelled something bad or Scar’s touching his computer. “Don’t really want to.”
Grian holds his gaze for just a second longer, then shrugs. “Okay,” he says, shoving Mumbo’s laptop aside. “Can I suck your dick now?”
—
Grian charitably decides to let it go. Mumbo, paradoxically, is perfectly okay with his fingers and dick in and around Grian’s ass—and vice versa—but hey, far be it from Grian to judge. He’s plenty satisfied. So a week goes by, and it’s Mumbo who brings it up next.
“Do you want to eat my ass?”
Grian pulls off of Mumbo’s dick with a slurp, swallowing all the excess saliva in his mouth and already moving to push Mumbo’s legs up higher. Then he thinks a little more about the tone of the question, and pauses.
“Do you want me to eat your ass?”
“No,” Mumbo says. “Er, yes? Well, no. But I wanted to know if you wanted to. If you like it.”
Grian sits up on his knees so he’s not face-to-face with Mumbo’s cock and considers his words carefully. “I don’t want to do anything to you you don’t want me to do to you.”
Mumbo wrinkles his nose. “But—“
“But—“ Grian cuts him off, “—with a partner who’s also into it? Yeah, I like doing it.” He shifts his weight till he can grab Mumbo’s chin, tilts his head up till he looks Grian in the eyes. “That doesn’t mean I feel like a piece of our sex life is fundamentally missing because you don’t want me to eat your ass, for the record.”
Mumbo considers for a moment. He takes a breath to speak three separate times before the question finally comes out. “Does it…feel good?” He’s blushing, high on his cheekbones.
Hmm. Maybe Mumbo’s a little more into this idea than he wants to admit to himself. Well. No harm in answering his question.
“Mumbo.” Grian lets his grin spread wide. “Mumbo, Mumbo, Mumbo. It feels amazing. Some people can even come untouched from it.”
“From your tongue?” Mumbo asks, sounding skeptical.
“And fingers,” Grian reassures him.
“Interesting.” Mumbo says. He’s doing a very bad job of pretending he’s not turned on. Grian pulls him in for a quick kiss before pushing him back down onto the bed and pulling Mumbo’s hand towards his ass.
“Now, you wanna show me how fulfilling and complete our sex life is?”
Mumbo rolls his eyes, but when Grian hands him the lube his kisses down Grian’s neck are full of intent.
—
Mumbo’s desk is in the corner opposite his door, so when Grian barges in he can see what’s playing on his computer. He can’t see Mumbo’s cock in his hand, but it’s pretty easy to extrapolate. The bottom doesn’t really look like Mumbo (nobody really does, it’s a pretty unique mustache) but the man with his head between his legs? Yeah, that could totally be Grian from behind.
“I’ll…come back later,” he says, watching Mumbo’s face pass from peach to tomato.
“No, Grian—“
“Enjoy your journey of self-discovery!” he calls behind him, pulling out his phone to text Scar about their homework instead.
—
“Hey, G!”
“Hey, Impulse. Hey, Tango.” Grian balances his plate on one hand, pulling out his chair with the other so he can sit down next to Mumbo and lean over to kiss his cheek. “Hi.”
“Hi,” Mumbo says. He always goes so red when Grian kisses him in public. It’s cute. Tango gags. “How was class?”
“Good, but tell Doc I still need his help for the final project thing with the solar panels.” Grian takes a bite of his sandwich, tries to slit open his orange with his bitten-down fingernails, gives up and hands it to Impulse instead. “How was AI?”
“Good,” Mumbo and Tango enthuse in creepy synchronization. Impulse just groans.
“I don’t know how you guys like it so much, it feels like it’s all, like,” Impulse hands Grian back his half-peeled orange so he can gesture wildly. “I feel like everything is in one ear and out the other with him.”
“You’re just not thinking about it the right way.” Tango turns sideways in his chair to face Impulse, and then they’re bickering on the other side of the table. Mumbo turns to Grian and grins.
“Do you think it’ll wind up actually being useful for Grumbot?” Grian asks, only half paying attention to Mumbo’s response. He hooks his thumbs into the top of his orange, instead, pulls it apart just a little and circles his thumb around the outside.
“—but I think it’ll be good to have something besides pre-programmed phrases, you know? Or at least the ability to recognize which phrase to use for the question being asked.”
“Mhm.” He keeps his eyes on Mumbo, and slowly brings the orange up to his mouth, lets his tongue circle around the outside where his fingers just were. Mumbo’s eyes drop to Grian’s mouth and go wide.
Mumbo keeps talking—kind of—and Grian takes it as a sign to up the ante. He sticks his tongue inside, fucks it in and out a few times, goes back in with two fingers—
“What are you doing.”
Grian rips the orange away from his mouth. Mumbo looks half horrified and half turned on. Tango’s clearly trying not to laugh: Impulse’s jaw is practically on the table.
Grian tosses the pulverized orange back onto his plate and takes a very casual bite of his sandwich. “Nothing,” he chirps through his mouthful. “What was that about a spaceship, Tango?”
—
Grian’s just seated himself. Mumbo’s fingers are digging into his hips, and he hasn’t started moving yet but there’s quiet, anticipatory pleasure radiating out from where he’s spread out and split open.
And then Mumbo opens his mouth.
“What do you like about it?”
Grian doesn’t try to pretend he doesn’t know what Mumbo’s talking about. He also doesn’t try to hide his eye roll this time.
“Complete hypothetical, of course?”
“Maybe?” Mumbo tries, grinning sheepishly up at Grian. He shifts his hips slightly, and Grian inhales sharply. Alright. Game on.
“You wanna know how I feel about it?” he asks, shifting his weight so he can plant his hands on Mumbo’s shoulders. He leans down, brushes a kiss against Mumbo’s lips. Mumbo nods mutely when he pulls away, eyes wide. Grian grins, and lifts himself up.
“I love it. I love putting someone on their hands and knees, and licking them out, and fucking them with my tongue and fingers, and driving them crazier and crazier till they’re begging me to let them come.” He fucks himself slowly, chest against Mumbo’s.
“And would you?” Mumbo asks, sounding strangled. Grian presses a kiss to his pulse point and clenches the next time he rolls his hips downward.
“Not yet. I wouldn’t touch their cock: I’d just keep going till their elbows give out, and they’re shaking, and I’d keep licking them and touching them till they have no choice but to come on my fingers.”
“Ah,” Mumbo croaks. “Right.”
Grian hides his smirk in the crook of Mumbo’s neck before he sits up and starts leaning to the side till Mumbo gets the hint and rolls on top of him. “Hypothetically, of course. Come fuck me.”
“Of course,” Mumbo murmurs, pushing his cock back into Grian in one long slide. “How do you want it?”
“Hard,” Grian replies, digging his heels into the vicinity of Mumbo’s kidneys. He reaches up to brace his arms against the creaky fake-wood headboard, lets his mouth fall slack and settles in for the ride.
—
“I want to do it,” Mumbo announces. Quietly announces, because this nook of the library is only occupied by the two of them and a stressed-looking freshman with a lanyard around their neck pecking at a laptop. Grian blinks owlishly at Mumbo.
“You can’t do my crit. You don’t know what a hyphen is.”
“I—“ Mumbo’s flush fades a bit, taken aback. “I know what a hyphen is.”
“Wrong kind of hyphen.”
“I don’t want to do your crit.”
“Glad that’s settled, then.” Grian turns back to his tablet, picks his stylus up again and tries for the fifth time to get his angle right. As he expects, Mumbo’s only quiet for a few seconds.
“I meant the other thing. The. Um. I—I want to—or, really, I want you to—“
Grian forces himself to keep his eyes on the screen, hold the stylus steady in his hand. If Mumbo really wants it—wants the thing that Grian thinks he wants, anyway—Grian’s going to make him say it. “Want me to do what?”
“You know,” Mumbo says, barely above a whisper. Grian does know. “The thing.”
“Mumbo.”
“Grian.” Mumbo’s eyes dart towards the other table. “People.”
“You brought it up!”
They stare at each other, red-faced stalemate for a breath before Grian grabs his tablet and shoves it into his bag.
“We’re going to yours.”
Mumbo, bizarrely, looks back down at the laptop, textbooks, and loose papers scattered around his half of their table. “I’m not—“
“We’re going to yours,” Grian repeats, leaning across the table to retrieve a rogue pen and pulling back just enough to put himself level with Mumbo’s ear. “And I’m going to?”
“Eat my ass,” Mumbo breathes, eyes screwed shut.
Grian presses the pen into his hand. “Let’s go.”
—
Grian fiddles with his phone while Mumbo showers—upon his insistence, not Grian’s, and yes, Grian, alone please. He’s not hard: hasn’t done anything, hasn’t even taken off his pants or run a hand over himself, but there’s warm and syrupy arousal twisting down low through his gut. Maybe he should take off his pants.
He starts touching himself when he hears the shower shut off, just cups himself through his boxers with his wrong hand, keeps his phone in the other and feels himself start to swell.
Mumbo finds him like that when he slips back through his bedroom door, flushed warm with a towel wrapped around his waist. Grian takes his hand off his cock, beckons him over to the bed and sits up for a kiss.
“Iskall says if we keep him awake he’s going to throw Grumbot into the pond.” Mumbo mumbles into Grian’s mouth. Grian pulls back from their kiss to grin, and snakes a hand down to fiddle with the edge of Mumbo’s towel till it drops to the floor. His other hand moves up, gliding across Mumbo’s pecs to his neck and face.
“Think we’ve paid him back enough for the kitchen thing yet?” he asks, scratching gently through Mumbo’s hair with the pads of his fingers. Grian pulls him forward, moves aside till they’re facing each other, laying on their sides on the bed. Mumbo shudders theatrically.
“Definitely not. I still can’t make eye contact with Stress.”
“Don’t worry about it, then,” Grian murmurs, pulling Mumbo into another kiss. “Your son is safe.”
“Mm,” Mumbo says, and then neither of them says much of anything for awhile. Grian keeps his hand in Mumbo’s hair, presses up into the weight of Mumbo’s hand on his hip. When Mumbo breaks their kiss for a deep breath, hard against Grian’s stomach, Grian pushes him onto his back and gets to work.
Slow lines of kisses, lips and tongue and teeth on Mumbo’s jaw, neck, the spot underneath his ear that makes him shudder underneath Grian, cock twitching where it’s pressed against Grian’s thigh. Grian feels Mumbo’s big, warm hands at the waistband of his underwear when he bites gently at Mumbo’s collarbone, and kneels up to slip them off one leg, then the other.
When he settles back down, he plants a hand on Mumbo’s chest and tilts his hips back so his cock is lying against Mumbo’s.
“Still want this?” he asks, running his hands across Mumbo’s chest, up and down and up again, reaching over to the bedside table to grab the lube and place it next to Mumbo’s knee.
Mumbo nods, screwing his eyes shut. “Goodness gracious. Yes.”
“Kay,” Grian laughs, and slides down till he can lie on his stomach between Mumbo’s legs. He pushes Mumbo’s legs up, higher and higher, keeps going till Mumbo’s knees are at his chest and Grian can reach in to grope his ass.
“I feel ridiculous,” Mumbo announces from above him.
“It’ll pass,” Grian says distractedly. He squeezes Mumbo’s ass harder, and leans up and in to press a kiss to the head of his cock where it’s peeking out of Mumbo’s foreskin.
He doesn’t do enough to really get Mumbo off, just teases with lips and tongue on the head and open-mouthed sloppy kisses down the shaft till Mumbo’s cock and balls are shiny with saliva and he’s breathing hard above Grian. At some point, Mumbo takes a pillow from underneath his head and presses it to his face. Grian keeps his mouth away from Mumbo’s entrance, just presses the pad of his thumb against his taint till Mumbo moans, teases till Mumbo’s cock is flushed red and twitching, then leans down, spreads him open to press a quick, closed-mouth kiss to his hole. Mumbo’s chest is pink. His arms are shaking where they grip the pillow.
“You look good like this,” Grian teases, digging his nails in just a little harder to the fat of Mumbo’s ass. “We should do this more often.”
“We have to do it for the first time first,” Mumbo points out, voice muffled.
“Touché,” Grian says, keeping the stream of air going so he can lean in and breathe warm over Mumbo’s hole to watch it twitch. Mumbo groans into the pillow, and Grian stifles a laugh.
He goes back to Mumbo’s cock, sticks out his tongue and licks at the head again before trailing down along the vein underneath, lets saliva pool in his mouth and tongues at Mumbo’s balls before gently cupping them in a hand and leaning in to lap at what’s underneath.
Mumbo breathes in hard when Grian swipes the tip of his tongue over his hole. It’s a little red, already a little puffy. Grian tastes soap, just barely. Underneath it, though, with his head shoved between Mumbo’s legs like this he can smell musk, a little sweat, clean and healthy and Mumbo. Grian focuses on lapping at Mumbo’s hole to keep from inhaling hard.
Grian pulls back, just a bit, kisses Mumbo’s entrance again. “How’s it feel?” he asks.
“Good,” Mumbo breathes. “It’s good, Grian. Keep going?”
Well. Who is he to refuse?
Grian gets bolder: long, broad swipes with his tongue from just behind Mumbo’s balls to nearly the base of his spine, a thumb rubbing at Mumbo’s prostate from the outside while he presses the tip of his tongue inside. Mumbo moans above him at the first breach, and it spurs Grian on, fucking his tongue in and out and pressing harder on Mumbo’s taint.
When Mumbo relaxes enough for Grian’s tongue to easily slide in and out, Grian reaches for the bottle of lube beside him and slicks up two of the fingers of his right hand. He goes to close the bottle, but—
Hmm. Better idea.
He lubes three fingers of his left hand as well, and shoves it down between his legs.
He presses one finger into himself and one finger into Mumbo at the same time, licking around the edges of Mumbo’s entrance and searching for his prostate. Mumbo’s hole is sloppy with spit and lube, and Grian’s mouth makes a ridiculous noise when he tries to latch on to the skin of Mumbo’s ass, but Mumbo just moans louder.
Grian doesn’t have a hand free to make him do it, two fingers scissoring in his own ass and other hand busy with Mumbo, but Mumbo seems to read his mind anyway, fisting a hand into Grian’s hair and holding him in place to ride his tongue and finger. Grian closes his eyes, sticks his tongue out and lets Mumbo use him, wet and messy and not at all gentle. He sticks his last finger in himself and gasps against Mumbo when they brush against his prostate.
When Mumbo’s moans turn to babbling close, Grian, please let me, Grian pulls back and slips his finger out of Mumbo. He looks up, locks eyes with Mumbo, who’s tossed his pillow aside to moan to the ceiling. Grian can almost see himself: face flushed, hair messy. He’s sure his lips are swollen. He licks them.
“What did I say?” he rasps out, and clears his throat before trying again. “What was I going to do?”
“Make me, er,” Mumbo whispers the last words, as though they’re any dirtier than the noises he’s been making, “come on your tongue.”
“Right!” Grian snaps his fingers, as though he’d forgotten. “I was going to do that.”
Mumbo blinks once, like he’s working hard to get Grian’s words through his brain. It registers suddenly, and his hand is shooting up to tangle in Grian’s hair again. “No, Grian, no, you have to, please—“
“I have to what?” Grian asks, holding Mumbo’s cock steady and rubbing his thumb against the underside. “You’ve gotten the rimming experience. Congratulations!” He shifts slightly, pulls away as much as he can without drawing attention to the arm pinned underneath him and the three fingers in his ass. Mumbo chases him, sits up slightly and reaches out like he wants to yank Grian back towards him. Grian pauses. “Something you want?”
“Grian,” Mumbo strangles out.
“Mumbo,” Grian replies, scissoring his fingers and smiling to keep from making a face.
“I—you—“ Mumbo sighs, runs a hand over his face and looks sheepishly at Grian through his fingers. “Make me come? Please?”
“Fine,” Grian sighs. “Pass me the lube?”
Mumbo nudges it back towards Grian. He opens it with his free hand and squeezes a dollop directly onto the head of Mumbo’s flushed cock.
“Cold,” Mumbo hisses through his teeth.
“You’ll live,” says Grian. Without much ceremony, he strokes Mumbo once to spread the lube, pulls his fingers out of his ass, kneels up—ignores Mumbo’s confused whine—and sits on his cock.
Oh, fuck.
“Grian,” Mumbo gasps, hands flying to Grian’s hips and head falling back. Through the haze creeping in on the edge of his vision, Grian sees a purple bruise lurid on his jaw. “God, you’re so…I—can I move?”
“Nope,” Grian wheezes, blinking fast and shaking away the blackness haloing his field of view. “I’m making you come.”
He pulls Mumbo’s fingers off his hips, guides them to his chest instead and leans forward so Mumbo’s cock feels less intimidatingly gigantic inside him. Mumbo nearly sobs when Grian pushes up and forward on his knees till he’s stretched out and open around the head of Mumbo’s cock, then drops back down to take him back in.
Grian rides him fast, rocks between the feeling of Mumbo’s cock nudging against his prostate and Mumbo’s hands, one pinching his nipple between two fingers and the other gliding up to cup his pectoral. He revels in the burn in his thighs for awhile, forces his eyes open to look at Mumbo wide-eyed and gasping below him to spur him further, longer, faster.
Eventually, though, his knees are screaming and he’s losing his breath, and not close enough to the precipice to ignore it and push forward. He fumbles for the lube instead, warms a puddle of it in his hand this time before messily spreading it across his cock and Mumbo’s stomach.
He flops down onto Mumbo, nestles his head into the crook of Mumbo’s neck and closes his eyes.
“Fuck me,” he whispers, pressing a kiss to the skin in front of him.
Mumbo groans, bending his knees to plant his feet on the bed before experimentally shifting his hips up into Grian. They both moan, this time—Grian clenches down at the slide of his cock between their stomachs—and then Mumbo takes a deep breath and starts to fuck him.
His eyesight is doing strange things again, but Grian soldiers through the feeling of Mumbo driving through his stomach, through the feeling of skin and wetness against his cock, to lean up on his elbows and stick his tongue in Mumbo’s mouth.
Grian tries to hold himself still as they make out, flushes down to his stomach at the thought of Mumbo using him like a toy to stick his cock in, but the slide of his cock against Mumbo’s stomach is too good and he can’t help but squirm into it. He settles for pulling away from Mumbo’s mouth instead, nipping at his neck as Mumbo’s thrusts get harder and sloppier.
“I’m gonna come,” Mumbo gasps into his ear. “Can I come?”
Grian manages a strangled “mmhm,” snakes a hand awkwardly behind himself to press the tip of his thumb to Mumbo’s hole before Mumbo’s gripping his hips hard enough to bruise and shouting to the ceiling as he pulses inside Grian, bucking his hips up once, twice more before stilling.
Grian waits.
Mumbo takes two deep breaths before he’s pushing Grian back up to sit, cock still hard inside him and taking up space in his lungs. Mumbo grabs for the lube, gets more in his palm and takes Grian’s cock gently in hand.
“Don’t move,” Mumbo tells him quietly, and hot arousal skitters down Grian’s spine. “Or, er, I—try not to move.”
Then he’s taking Grian in hand, stroking slowly, and there’s too much lube, too much, it’s slicking Mumbo’s hand and dripping down Grian’s balls, and Mumbo’s softening slowly inside him and it’s not enough, it’s not enough—
Mumbo lifts him, slips his cock out and shoves three fingers back inside Grian before he can make a noise, crooks them and nails his prostate fast and hard while his other hand speeds up around Grian’s cock.
“Pinch yourself,” Mumbo commands, voice low and deep as he works Grian over, and Grian sobs dryly as he slides his hands up to his chest. “Like that, yeah, come on—“
“Tell me to come,” Grian gasps, toes curling as he pinches his nipples, and Mumbo’s hands stutter.
“I—yeah, Grian, you should—I mean. Grian,” he tries again, voice lower, less shaky, looking at Grian with dark, dark eyes. “Come for me?”
And Grian shakes apart.
He spills over Mumbo’s hand, an errant streak or two landing on Mumbo’s stomach. His eyes can’t seem to close: tears well in his eyes and slip down his face but Mumbo’s right there, right in front of him, stroking Grian through his orgasm and bringing his thumb to his mouth to lick Grian’s cum off. A painful aftershock shivers through him as Mumbo brushes against his prostate again, and Mumbo guides his fingers out with a whispered apology.
They mop themselves off with tissues before collapsing side-by-side on the bed, still breathing hard.
Grian rolls over, eventually, presses his chest to Mumbo’s side and tosses an arm over him.
“Everything you dreamed it would be?”
“I,” Mumbo says, uncharacteristic seriousness in his voice, “am doing that to you next time.”
“Be my guest,” Grian yawns, pulling Mumbo’s arm underneath his neck.
—
“—and he thinks that I programmed in the responses myself because of how sarcastic it is, but I didn’t, Grian, it just turned out like that on its own.” Tango plonks his head down on the table, scrubbing his hands through his hair. Impulse pats Tango’s shoulder comfortingly, other hand twirling a forkful of pasta.
“If anything, you should get extra credit for making an AI with a personality,” Grian says through a mouthful of sandwich. “Hi, babe.”
Mumbo squeezes Grian’s hand as he sits down. Tango keeps complaining—it wasn’t supposed to just be HAL 9000, it just turned out that way, but he thinks—but Grian’s eyes are fixed on the orange Mumbo’s carefully peeling.
Without making eye contact with Grian, Mumbo raises the peeled orange to his mouth…and sticks his tongue inside it.
Grian drops his sandwich, stands up and swings his backpack over his shoulder.
“Okay, bye, guys!”
Impulse pauses mid-bite. “You’re leaving?”
“Yep!” Grian replies, tugging on Mumbo’s shoulder and handing him his satchel. “See you later!” Mumbo looks mournfully at his untouched sandwich, but stands too.
“But Mumbo didn’t even—“
“Bye!”