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Three's Company

Chapter Text

Every day she frequented the coffee shop.  Grillby gave a soft sigh as could feel himself burn a little brighter and hotter just at the thought of her.  Her large amber eyes, her long flowing purple and pink hair, the curve of her smile…

Grillby wasn’t sure what initially attracted Sai to him.  Perhaps it was her voice and how she would ask for her coffee?  Or perhaps it seemed like she genuinely seemed happy to see him or any of the staff that worked at the GalaxyBucks?  But she was so kind and gentle… her twinkling laugh always at the edge of her tongue…

“Grillby!  We have a lineup!” Tracey called out to him, disrupting the monster’s thoughts.  He had been putting away the fresh stock in an excuse to fantasize about her but it seemed as if customers always knew when he didn’t want to be disturbed.  With a sigh, he put down the box of cups that he had been putting away and abandoned his daydream as he walked through those swinging doors, seeing the line stretch from the cash registers to the bathroom…

And came face to face with his daydream.

Stars… did she know that he was thinking about her?

He waved her over, his fake customer service smile gone, a real true smile in its place.  She grinned back at him, stepping up to his cash register.  “Hey Grillby, busy day?” she asked, winking at him.  The GalaxyBucks he worked at was close to the shopping mall and was close to various other businesses.  It was always busy.

‘You know it.’ he signed back to her.  Fire monsters were naturally mute other than some primal noises that they were able to make.  Grillby had mastered sign language to communicate with others.  ‘You know it.  The usual today?’

Sai nodded as he grabbed the clear cups that he would use for the mocha frappuccinos.  She was one of a few monsters or humans that could understand him without resorting to his paper signs.  “I think it is a sign that I’ve been coming here too long or frequently if you know my order off by heart.”  She said with a small laugh, getting out her wallet.  “But my boss always prefers your coffee over all the others… and I have to say that… that I do.” she said, her cheeks glowing with a soft pink.

Before she could notice, Grillby typed in his code for his staff discount.  She hadn’t noticed yet that she always saved a couple extra dollars when she came in to see him.  ‘Well it is always a treat to see a friendly face,’ he signed to her, taking her money from her.  Before she could say anything else he began to mix up the drinks in just the way that only he could.  An extra half a squirt of flavouring, an extra dribble of cream and an extra moment on the spinner.  He handed over the coffees to her, much to her delighted grin.

“Thanks again Grillby,” she said as she dropped some spare change into his tip jar. She turned and began to walk away.  “I’ll be back”

I hope so, Grillby thought to himself, watching as she walked away.

“Would you just ask her out already?  It’s obvious that you like her.” Tracey said to him, hands on her hips and a slight look of annoyance on her face.  Jolting from his thoughts he looked around the restaurant.  The line was gone now.  In the time that it had taken for him to serve Sai, Tracey had raced through the rest of the customers.



* * * * *


“I’m back,” Sai called out to Gaster.  Pushing some papers out of the way, she placed their coffees down on one of the many tables that were placed in the lab.  “There was a bit of a lineup today, but Grillby made them, so they will be worth the wait.”

Gaster didn’t turn around from the weather map that he was inspecting.  Instead, he allowed himself a small smile as he heard her already running around the lab, throwing on her lab coat over her dark turtleneck and slim jeans.  “You know that I’ve never been much of a stickler for how much time you take for your breaks.” He told her.

Sai snorted.  “I’ve heard what you say to your secretary if she is thirty seconds late in coming back.” She countered, coming up to stand beside him.

“That’s because she has a longer break than you, has made it a habit of coming in late, and she doesn’t finish all her work before she leaves for the day,” Gaster said, a single violet eye light moving to look at her.  “You, on the other hand, have a wonderful work ethic.  One that I wish more of my assistants had.”

Sai blushed at the small praise.  “What can I say?” she said.  “I was raised in the old-fashioned way.  Work first, play later.”

Gaster smiled at her before making another small mark on the large map.  The rainbows were becoming more and more frequent.  If Gaster was a man who believed in symbolism, he would have believed that it was a sign of something coming.  But, Gaster was not.  He was a man of science.  The rainbows were pretty, and probably due to some rain that evaporated before it hit the Earth.

The strange men in armour that appeared after them, nothing more than wide-spread hallucinations.

Sai handed him his coffee and together they looked at the weather map, wind currents and weather patterns, trying to find some proof to his hypothesis.  At the end of the day, there was little progress made, and even Gaster was wondering if perhaps his rain theory was running on steam.

“Tomorrow is another day,” Sai said at the end of the day, grabbing her coat and purse.

Gaster smiled, watching her pull her hair out of her collar and watching it cascade down her back… “I can already tell it will be a good one.”


* * * * *


Grillby looked up to the door at the bell, slightly hopefully.  It had been a rough day already for him.  One of the anti-monster humans had come in and started throwing himself a tantrum about Grillby working in the establishment, almost as if Grillby didn’t have the right to work there.  It had almost gotten physical, but luckily the policeman behind the “gentleman” had helped detour the situation.

To his delight it was Sai.  Her hair was slightly tousled from the wind, her eyes slightly puffy and red… wait.  Red and puffy were not good signs, especially with humans.

He looked at her with concern as she came up to the window.  She still bravely smiled at him.

“Hey Grillby,” she said.  “Can I get the usual please?”

Grillby grabbed the cups but gestured to his eyes, asking her what was wrong.

“Oh, my stupid car died on me as I pulled into a parking spot.  I suppose I should be grateful that it died there and not on the highway but…” she sighed. “I already called a tow-truck, but they can’t make it out until after five…” her hands shook slightly as she handed him her change.  “I just… I don’t know what to do.  Gaster isn’t picking up the phone and I need to make it back to the lab and…”

The fire monster snuck a quick look at the clock.  ‘I am doing an early shift today.  I only have a few minutes left.  How about I mix up your drinks as you leave Gaster a message, telling him you’ll be late, and then I’ll drive you over there?’

Her eyes widened.  “Oh no.  I couldn’t possibly ask you to do that for me…”

‘Please?  I insist. I want to help.’

Sai bit her lip, weighing her options.  “Well.  If you’re sure, then I would love a ride.”

Grillby felt his soul skip a beat.  ‘I am very sure.  I’ll be happy to help.’


* * * * *


The few minutes seemed to take forever.  Sai sighed and played with her phone, wondering why Gaster hadn’t called her or at least messaged her back.  Sure he wasn’t too picky when she came back from her break, but still.  It would be nice if he showed that he was a little worried, a little concerned about what happened.

She supposed that it was only a matter of time until the clunker had wheezed its last breath.  The car had been in her family since she could remember.  She could remember when her dad was driving it and someone rear-ended him and tried to flee, leaving the apple-sized dent in the bumper.  Both she and her brother had first learned to drive in it (that was its own horror story).  And now…. where was she going to find the money for a new one?  Her pay at the lab was good but wasn’t enough to add car payments to an already stretched budget.  Rent and groceries took up a large chunk of her paycheque, and she was lucky that Gaster always gave her money for coffee.

Perhaps she should look into a second job for when she was done at the lab.  She heard that strippers made a lot of money…

‘Ready?” Grillby asked her, coming up to her with his jacket slung over his broad shoulders.

She nodded.  Gaster had been a little short tempered today.  She hoped that he was ok.

For a few minutes, Grillby and her drove in silence, watching the familiar scenery go by.  “Hey, you’ve never been where I work.  How about I show you around a little bit?” Sai offered.  “It’s the least that I could do after you gave me a ride.”

Grillby’s eyes seemed to sparkle slightly and he nodded happily, never taking his hands off the wheel.  She supposed that this would be one time that it would be a disadvantage to be mute.

Sai had grabbed the parking pass from her car before they had left the coffee shop, allowing Grillby to park in the staff parking lot.  “Now just remember that everyone here is a little strange and nerdy.” She warned him as she scanned her pass.

‘Sai, I literally work with hipsters, students and those who wish to escape our reality.  Nothing surprises me anymore.’

She had to laugh at that, missing the secretary’s startled face and gestures when she entered Gaster's lab.

The first off thing that she noticed was the smell.  It was pungent and musky, like an earthly aftershave.  The atmosphere of the lab was positively dripping with it.  It both disgusted Sai… and intrigued her.

“Gaster?  Gaster are you in here?” she called out, eyes watering at the scent.  “Are you ok?”

A firey hand grabbed her shoulder.  Grillby.  ‘Monster heat….’ he signed, his eyes narrowing slightly and the flames burning brighter.  A smoky scent began to intertwine with the earthy one.  ‘And it’s contagious.’

A dark chuckle was heard from the depths of the lab.  Gaster appeared, slowly walking towards them, his violet eyes bright and flaring, sweat pouring off of his bones.  “He’s right…” he had caught Grillby’s signs from where he had been near the vent of the lab, desperately seeking some cold air for relief.  “I’m in heat… and it seems to have triggered his own too… but I can smell that it affected you as well.”  Grillby nodded, his nose flaring for a second before looking at Sai.  “You should get out while you can, Sai.”

Sai gulped slightly, looking between the two monsters.  They were both handsome monsters in their own way.  Gaster was lean and intelligent looking, with an air of confidence around him.  Grillby was tall and broad, oozing with kindness.  Although she had never vocally said anything to the two of them before, she had always felt a strange pull, an attraction of sorts, to the both of them. 

“I want to help.” She said simply, knowing that they would understand and that she would know what power that that simple sentence held.

In moments she found herself being lifted up off of her feet, hot arms embracing her and pulling her back towards a hot chest.  Grillby ducked his head, kissing her deeply, tongue already invading her mouth, tasting her.  She gasped in surprise before making a small, content noise, eyes already closing.  Gaster was not content in watching the make-out session though.  He came close to the couple, roughly pulling Sai’s jeans and panties from her, a bony finger probing at her entrance as his teeth grazed her thigh.  Sai bucked and squeaked, but Grillby did not break the kiss or release her, leaving Gaster to gently test her.  A single phalange thrust in and out of her before another joined it, gently stretching her most intimate of areas out.  Before long a tongue joined his fingers, slurping noisily at her juices.  Sai moaned in pleasure, managing to break free of Grillby’s kiss long enough to catch a short gasp of air.  “Come on,” she gently pleaded.  “I’m ready for you.”

Gaster's tongue withdrew from her wet core and stood, looking at Sai with distant, but mischief filled eye sockets.  Her juices were still smeared on his skull and teeth, the low lighting of the lab catching her wetness.  Before she could blush at the sight, Grillby leaned in close, his molten mouth opening to expose his own tongue, and he licked up some of her juices.  His eyes widened at the taste.

“Delicious, isn’t she?” Gaster asked him.  Grillby could only nod, still holding tight to Sai, but looking at her with lust filled, hungry eyes.  “Shall we move onto the main course?”  In a smooth move, her blouse was pulled from her body, her bra soon following.  The two monsters let the offending clothing drop to the floor, taking her in slowly, savouring every inch of her.

As if choreographed, Gaster took Sai into his arms, allowing Grillby to pull down his own pants and boxers, as Gaster's own slacks fell to the floor.  The large rod appeared to be made of fire, just like the rest of Grillby’s body, and it stood erect with need, a small bubble of pre escaping his slit.  Gaster, on the other hand, had a slimy black tentacle that wiggled, rubbing against Sai and causing Gaster to hiss with pleasure.  It was already oozing blue magic, leaving little streaks of blue on Sai’s legs where it touched.  Grillby came close to them, sandwiching Sai between the two monsters, and grabbing her thighs, pulling them gently apart.  Grillby pressed against her the entrance of her core, her fluids dripping slowly onto his head, while Gaster’s slim tentacle pressed against her other hole.  Carefully, slowly, they entered her.

Sai hissed as she felt the two monsters enter her, but not with pain.  The hormones in their heat scent had made sure her body was well and truly prepared for the two of them.  No, already pleasure was overriding her senses.  Grillby slowly sliding in until his bottomed out against her cervix, spreading her core in the most delicious of ways.  And Gaster, she had never thought that anal could be so sinfully good.  There was no pain despite the breach.  The tentacle was well lubricated and slim, fitting inside of her like a glove.

She was well and truly full.

They gave her a moment, a small moment, to become adjusted to them before they began to move.  Grillby thrust slowly with his hips, withdrawing almost to his tip, before smoothly sliding in again.  Gaster held tightly to their little prize as his tentacle did all the work for him.  It thrust inside of her, the tip extending and retreating, pressing against her muscles.  Together, the two monsters moved in harmony, moving slowly at first.  She moaned loudly, wrapping her arms around the both of their necks and shimmering her hips slightly, inviting them to go faster, deeper.

Gaster gripped her hips, rearranging the angle of her hips for Grillby as his own tentacle readjusted.  Grillby wrapped his arms around Gaster’s pelvis, pressing closer to the both of them and his thrusts beginning to pick up and strength, causing Sai to see little stars behind her eyes as he continued to thrust into her.  The dark skeleton grinned as his tentacle became two.  One continued to move inside of her, building up the coil of pleasure deep inside of her.  The other tentacle stealthily made its way to her pussy, effortlessly finding her clit and beginning to stimulate her.

She began to scream in pleasure, her fingernails digging into bone and fire, causing them to also growl at the mixture of pain and pleasure.  They didn’t dare slow though.  They were so close… so close to the end…

With a loud shriek, Sai came suddenly, her body tightening around both the rod and the tentacle as the aftereffects of her orgasm rocked through her entire body.  This caused both monsters to hiss and growl, freeze in their movements and come as well.  Grillby completely filling and coating Sai’s core with his hot, magical cum, gradually warming her from the inside out, as Gaster’s tentacle released more fluid, lubricating her insides.

They panted together as they slowly came down from their highs.  Quivering knees and arms helped hold the three of them together, interconnecting the three of them even more intimately.  The skeleton and the flame monster both checked their smaller human.  Eyes sparkling and tearing, panting breath, skin flushed and sweaty, and her hair slightly damp with their excursion, there was only one identical thought in each of their minds:

By Asgore, I love this woman.