Gaster!Sans x Various!Sans [one-shots lemons]

Gaster!Sans x Original!Sans

Warnings:

Full on lemon here.
NSFW, touching, ecto-vagina
Also, there is a hint of cheesiness.

Gaster!Sans will be known as G.
———
Author's POV

"Babe."
"Ngh.."
"Babe. Hey."

Sans groaned, flailing his free arm around to try and swipe whoever was disturbing his peaceful nap. It felt like it was too early, and Sans didn't have work today, which meant he could sleep the whole time before returning as the owner of this famous five star hotel. Gods, he shivered at the thought of the piling amounts of stress that weighs him down as someone in that position. "Sweethearrrrrtt," Sans grunted, his mind hazy as he heard G, his prankster of a boyfriend drag out the letter "R" to purposely annoy him. "Wake up!"
"No, G. Go back to rest."
"...."
The room went silent once again, and Sans inwardly sighed in relief for the few seconds of quiet. But it was replaced with a slight worry that he has upset G from that. "Mnh.. G?" The lack of response made his stomach churn. Goddammit. G was too good at playing the cold shoulder technique, because in thirty seconds, Sans was sitting up and rubbing his eye sockets mournfully. "Morning, doll." Sans blinked, eyes focusing on G's bare figure right in front of him.
"Ah-! G, what the hell?" Sans jumped a bit from the specific lack of clothing G had, and the knowing smirk on his face told him that he knew something happened. He felt his skull flush a bright cyan glow, when he too, realized that he was practically naked except for the white blanket that was covering his pelvis area. What the fuck-
G clambered in top of him, his tall stature quickly taking over Sans' small figure as he nudged away the blankets. Sans couldn't help but stare at his white, porcelain bones. He was honestly getting slightly turned on. "Take a picture it'll last longer." G's teasing tone made his soul do a flip as he winked at Sans; who blushed harder that before as he tried to shake those impure thoughts.
(It's not like they haven't done "that before.)
He tightened his fists on the covers as G dipped his head down, calculating eyes scanning over him as he suddenly felt shyer more than ever. He looked away, observing the oh so suddenly interesting nightstand they had. G was close now, and he shuddered when he felt his breath on his neck, tickling him a bit. What was he doing this near? Sans wasn't about to complain. So he nervously gulped and tried to relax, legs on either side of G's hips, feeling the smooth silk covers of the bed. Just the two of them at home, the orange glow of the bright hours of the morning sun peeking through the curtain's slits and casting a light over both of them, making them both seem to glow. Gulping, Sans turned his face towards G's, only to let his lips lightly brush against his.
His breath hitched when he caught his pinpricks shining with love and want, his right pinprick glowing a bright flare of yellow and purple at the same time. Sans' blush deepened as G lowered his voice an octave down, the hint of sexiness made Sans feel his sins crawling on his back as he released a shuddering breath. "Sweetheart," G licked his lips as he spoke. "Could you be good for me?" His husky tone made him melt then and there, as he consensually nodded; the fuzziness inside him growing into an excited buzz of adrenaline. G proceeded to press their lips together, savoring the warmth that suddenly grew inside him, tilting Sans' head upward as he continued to deepen the kiss, his tongue probing his mouth until Sans parted it, letting out a small whimper as he met his tongue, pushing forward to get more open access. It was steaming now, the heat of G's touch left trails of fire everywhere he prodded; from tangling his fingers into his ribs, into slowly scraping downwards towards Sans' pelvis as he felt the magic pooling into the empty space. Sans gasped as he suddenly pulled away from the kiss, arching his back when G slipped in a slender finger inside of him; his warmth. G prodded his finger inside of Sans, pumping it in and out at an agonizingly slow pace as Sans tried to sloppily sync with it. The pleasure was building up, not enough to make him cum, but just enough to stimulate him farther. He writhed under G as he chuckled, giving a light kiss on his neck before whispering a short praise to him and slowly adding another finger, scissoring him to try and prepare him; this time earning a pleasant mewl and whimper. G was taking in Sans' sweet moans, feeling his wet pussy throb from need, his free hand molding his own pelvis. He let out a grunt as he occupied his mouth by leaving hickeys on his neck, grazing his sweet spot and nipping on it. He decided that he liked how helpless and vulnerable Sans looked, his expression made G's pleasure spark as the electric current traveled to his pelvis. His sexual magic stirred and formed a decently thick shaft. Feeling pleased with himself, he suddenly curled his fingers inside Sans, hitting his sweet spot and making Sans shamelessly moan out his name, as he bucked his hips and pressed himself into the pillows as he came, the sudden sensation had his vision turning white for a second before he was face to face with G. His bones were burning, heaving in his faltering breaths as he panted, gulping in air. He didn't realize that pleasure tears were rolling down his cheekbones before G wipes them away with a gentle peck on his nose, and half lidded entranced eyes made Sans blush harder.
G pulled his fingers out slowly, enjoying the look of Sans when he touched his sensitive folds, before completely pulling them out and bringing them to his face. It was covered in clear white fluid; his cum.
G licked his fingers clean, eyes shut and with a blush forming on his cheekbones as Sans' magic spiked up; again. His soul thumped when he saw G sit back, his cock hanging out as he put his hand around the shaft, rubbing it slightly until a bead of clear pre-cum formed at the tip. Sans stuttered when G relaxed on his knees, leaning back slightly as he showed the full view as he ran his hand up and down slowly, pulling in a sharp but silent gasp before letting out a breathy moan as his movements quickened, sweat trickling down his skull. Sans watched him, completely fixated on him and him only. The little details; Sans took in. The way his voice noticeably went to a slightly higher pitch when he was in pleasure, how his bones quivered, and how he didn't hold back his "singing" when he was in bed. Sans slowly kneaded his magic; his eyes shining. He didn't care: he was too turned on. Fuck, he was so wet. His own fingers feathered over his clit, and he bit his lower lip to suppress a moan. He was too sensitive from his last orgasm, and every touch seemed ten times more pleasurable than before. "Ah.. F-Fuck.. Doll.." Sans panted with him, eyes glued on G's movements as he tried to be in sync with him. G slowed down, opening his right eye to look at Sans.
He looked like a wonderful mess, touching himself like that. Even though he was still sensitive, he was fingering himself, in and out as he canted his hips. His mouth hung open, tongue hanging out along with his eyes rolled up.
G smirked from the disgustingly lewd moans he emitted, and he wanted to hear more.
"Lay down for me," G shrugged off the blankets on his shoulders, grinning widely. "And let me fuck you."
Sans didn't hesitate. He laid back, pulling his fingers out with a whine, furrowing his eyebrows. G shuffled towards him, his hands resting against Sans' legs as he willingly spread them further for easier access. The view was breathtaking: seeing Sans like this. He looked absolutely fucking delicious; and G loved that. He was going to wreck him hard.
Sans squeezed his pillow on his sides to brace himself. G rubbed his hard cock on his pussy, lubricating himself as Sans tried to push onto him; letting out a frustrated noise when G pulled away with a playful snicker. Sans hated how calm and composed G could be during sex and how he smoothly controls any situation. He wanted him to see the guy break. Maybe he'll get to top-
"A-Ah! Fuck!"
Sans yelped as G suddenly slipped his cock inside him, the burst of pleasure made Sans writhe and moan louder with the only distinguishable words were "Fuck," "More," and "Please." Along with a word that somewhat sounded like G's name. Goddamn, Sans felt so fucking good around him. When he was fully hilted inside, he gave an experimental thrust which resulted in Sans arching his spine and throwing his head back, entirely vocal now.
G continued with nine long thrusts, pulling out until only the tip was inside Sans and slamming back down. Sans' cries made G's sex drive rocket more, groaning as sweat poured from his skull. G didn't have the patience for the long thrusts anymore; which resulted in him only pulling out three inches away; before slamming back down. He was practically grinding on him.
Pleasure radiated through Sans as he pushed down when G fucked him roughly.
G slowed down, panting with a ragged breath as Sans shook a bit, before giving a whine and tried to further rock his hips from the loss of friction.
"Wait for a s-second." G put his right hand around Sans'  left leg, lifting it up on his shoulders. Sans squirmed to try to get into a comfortable position, eager to get back to action. "If I do this, I'll get to go,-" G plunged his dick hard into Sans, Making him moan out. "So much fucking deeper..!" G grunted, the pleasure made him go faster as his grip on Sans' leg grew tighter.
Sans moaned, hugging the pillow.
G felt him tighten around his cock, and , suggested by his voice getting  higher and his movements getting erratic, he was cumming.
And G knew he wouldn't last longer either. G leaned forward, catching Sans' mouth with his and slipping his tongue in as he moaned in the kiss. Sans pulled away, whining and moaning, "G! I-I'm cumming!" Sans felt his dick twitch inside him, sending a jolt up his spine.
Sans felt the knot in his stomach tighten, pure bliss radiating through them both as G canted his hips forward, reaching Sans' G-spot as he came.
Sans tightened around his cock, too tight to the fact G had to wait a bit for him to start moving again.
Sans yelped as he came hard, the knot breaking as he spilled his cum all over G's cock as he felt the sharp pleasure as he threw his head back. G moaned loudly, quivering as he came, Sans moving his hips to milk G's cock further. Sans panted softly as G dropped his leg from his shoulder, rubbing Sans' cheek lovingly as he whispered praises next to his head, the half passed out Sans barely listening as he snuggled into G's hand. His eyes were almost shut close, dripping cum from both of them flowed out of his pussy as G slowly pulled out, making Sans tense up from his raw ecto-flesh rubbing against his cock.
"Love you sweetheart." G kissed him affectionately, and Sans didn't resist, using what energy he had left to return it, wrapping their tongues around each other's. After what seemed like a minutes of passionately making out, G fell beside Sans, the bed rocking a little as Sans snickered sleepily. "You sleeping now?" Sans make a humming sound, shutting his eyes and letting sleep take over.

"G'Night then, Doll."