Chapter Text
Your office holiday party is tonight. Your hand shakes as you put on the finishing touches to your makeup. You keep tugging at the little red dress Sans had bought for you. It was very short, very tight, and very... unprofessional. Could you really go to the party like this?
"Where did you get this dress?" your lover nuzzles your neck behind you. Smelling your hair, she wraps her arms around your waist and hugs your curves.
"I bought it yesterday on my way back from the lab," you lie. You had been doing that a lot, but your lover is too distracted by the silky texture of the dress and the way it glides over your body. You purr as her hands begin to pull the fabric up until your dress is above your hips.
She slips one hand under your panties. "You're fucking irresistible in this dress."
You gasp as two fingers surround your clit and dip in slow circular motions. She nibbles playfully on your ear lobe, "I may have to cancel my date and go to this party with you, after all."
"I... told you... you can come." It's hard to concentrate as she pulls one of your breasts out of your dress and squeezes it roughly. Her nails digging into your skin, she presses her body tightly against your back. She's so... soft. So different from...
"And ruin your date with that skeleton? I'd rather not come between you and your boss. But I will remind him who you belong to," she dips her head down to your neck as her hand circles faster between your legs. She squeezes your breast again, bites into your neck, and starts to suck, hard.
"No...Ah!" You try to pull away from her mouth, but your knees go weak as the pain pushes you closer to the edge. You had a weakness for aggression and you'd be lying if you said you didn't enjoy her possessiveness. One of the best parts of this open relationship idea was that it had brought this side out of her more.
She enjoyed marking you.
She enjoyed the idea of others having you and not being able to do the same.
And you...
You enjoyed the tease.
She looks up at you in the mirror and enjoys her handiwork. You arch your back as the muscles in your stomach tighten. Her fingers increase their speed with an expert squeeze that has you cumming against her hand.
"Ahhhh!" You grip the counter to keep your balance and she kisses your shoulder blade as you shake in pleasure. Hugging you against her, she says, "You're so beautiful when you lose control."
You look up at the mirror and examine the crescent marks along your breast. Thankfully, she didn't break the skin; however, the new red hickey on your neck was not going to be as easy to hide.
"Your mine."
She turns you around and pushes you up on the counter. You wrap your shaking legs around her hips as she cups your face in her hands. "I love you." You're still panting a little as she takes your lips with hers. You breathe into each other's mouths, and she dips her tongue between your lips, claiming her territory.
You slide your hands under her shirt and drag your nails across her soft skin. She purrs and nibbles on your lower lip. "You have the most perfect lips, love. And their mine. Don't let bone boy forget it. Kisses are for lovers."
"I know. You trust me right?" you kiss her back and hate yourself as she nods. She shouldn't trust you. Because the truth is, you have been losing control of the situation since the moment you met Sans...
At first it had just been a casual fling of curiosity.
The first day you met, you shook his hand as he welcomed you to his team. You'd gasped at the electricity that raced up your arm from his touch. Everyone around you thought Sans had just played a joke - the old buzzer in the hand trick - but there had been no buzzer. You shook the feeling off with a small laugh, "Must be static electricity..."
He agreed with a "Sure, kid," but his eyes followed you the rest of the day. He caught you examining your hand that kept tingling even hours after he'd touched you. It was your first real exposure to magic.
You went home that day and studied all your old notes on monster physiology. It had been a required course in college since monsters had come back to the surface. You were in your junior year of your Physics degree when they emerged, and you had thought the class was a ridiculous requirement back then. As you flipped through the pages of your notes that night, you ate your words and silently apologized to your professors who had prepared your ungrateful younger self for your first job with a skeleton boss.
You learned that skeletons were some of the purest vessels for magical activity. It's how their bones stayed together (among other things). But there's was nothing in your notes about shocks. You started to examine you colleagues interactions with Sans, but they didn't exhibit your sensitivity.
You weren't the only one who noticed. The first few days you had to work closely with Sans to learn the routine. The hair on your skin raised at his proximity. When he was teaching you the computer system, you nearly jumped when his finger bones grazed yours on the keyboard. You apologized, but he barely acknowledged it as he stared at the goosebumps along you arm. You noticed his bones bumped into you a lot that day and you got the feeling he was running his own personal experiment.
Not wanting to be known only for your static jumps, you took matters into your own hands so that you could be taken seriously. It was summer back then, but you started wearing long sleeves and gloves to work. With practice, you successfully avoided touching him directly. You became excellent at dodging even the simplest of movements.
It became a game. You watched him watch you. You made him acknowledge your work by always volunteering to share the latest reports without your gloves on. His hand would touch yours as you passed him the folder, and you would shiver, biting your lip. You could see by the tension in his shoulders and the way he rubbed the folder in his hand that you were teasing him...
...and that had always been your favorite game.
After a few exchanges, curiosity got the better of him, and he got bolder. His hand lingered; his thumb rubbing small circles along your the back of your hand. You tried to pull your hand away, but his grip... was a lot stronger than you expected. "Describe it."
"I..." you didn't know where to start.
"Close your eyes, kid."
You bristled at the nickname but obeyed. You relaxed your hand in his.
"What do you feel?" His voice was so gentle, it threw you off. He was serious in his desire to know. This was becoming less of a game... Your boss's hand covering your own...
You took a deep breath. That was the first time you noticed the way he smelled like those ketchup packets he snacked on and... smoke? You'd never seen him go on a cigarette break. Did cigarettes even effect a monster without lungs?
Stop rambling to yourself. Feelings. He was waiting for your...
"Your magic pulses," you start. "I'm... sensitive to its wavelength, I guess? Sometimes you shock me but I don't know - Ah! you just did it!" you exclaim as you open your eyes and read your answer in the desire within the lights of his eye sockets. "Oh..."
Primal. That was the only way to describe that moment. His magic rippling through the nerves in your hand and traveling up to the beat of your heart. His eyes held a question you had seen so many times in your life, but never from a monster. All he needed was your consent...
But then a knock came at his door and you both jumped. He released your hand. And awkward moment lingered as you both remembered where you were... and who you were.
He's my boss.
Still, if you got your lover's permission...
"Perhaps," you licked your lips that had gone dry under his gaze. "Perhaps, we could continue these observations later this evening?"
Sans nodded, not trusting himself to talk. You stood up and opened the door to let the next person in. "I'll have the rest of the reports on your desk at the end of the day, boss."
And that's exactly where he found you later that night, on his desk, waiting for him. You laid out the rules of your lover, "No kissing and no visible marks." Sans found no problem with either. It was the perfect arrangement for a casual fling. At least, it would have been...
That night, he unraveled your nerves with his magic. His kisses burned down your chest and between your legs. And that's when you realized that magic left invisible marks that you hadn't known existed. Your world imploded when he revealed his tongue, blue, glowing, and made of concentrated magic that consumed your very core the first time it touched your skin.
"I've never met anyone so sensitive," he chuckled as you orgasm the first time his tongue found your clit. "How many times can you do that?"
You lost count as you ripped off his shirt and clawed at his bones. His tongue was unrelenting until you couldn't breathe. You had to beg him to stop and still he persisted, "You can take more. Ride it. Open yourself to my magic."
You lost yourself in waves of pleasure as your last orgasm lasted for minutes? an hour? You knew it was an exaggeration, but all you could see was blue light when you closed your eyes. Your throat lost the ability to even make noise was your mouth echoed an impossibly long "o" that left you panting and gasping for air. You had no energy to wipe the smug look off his face, nor did you bother to move as he took down notes in the journal beside his desk. You let the soft fall of pencil scribbling on paper almost lure to sleep.
Eventually you regained the will to move, and you snatched the book out of his hands. He let you flip through it. He'd been writing down simple observations of your reactions to his touches for a while. He had theories, crossed out hypotheses, but the last page he was writing in didn't have much aside from a crude orgasm tally and a rough sketch of you lying sated and naked on his desk. The words "Minimum Effort. Maximum Result" was scrolled on the bottom.
"You're a naughty monster."
"Are you sure you aren't one as well?"
"I see that's one of your theories."
"You fuck like a monster."
"We haven't technically fucked. Can you even-?"
A bright blue glow tented in his pants. "Oh... yes you can. Is it like your tongue?"
Sans shrugged, "Bigger, thicker... based on your earlier performance, I don't think you could handle it, kid."
You wrinkle your nose at the term, "What I can't handle is that nickname."
"Hm, how about "bunny" for the amount of times you hopped those hips against my mou-"
His phone rang, and he froze. You realized it was just a text. Sans explains that it's his partner. "He gets... distracted for long periods of time. I'm allowed to do what I want while he's like that, but when he texts..."
"I understand. I need to get home anyway."
But as you head home, you can't shake the tingling sensation that clung to your skin like a magical residue. You were sure your lover would feel it as she hugged you or cuddled you that night. But she didn't sense anything. She just asked you if you had fun, and you nodded. She left long claw marks down your back that night. "So next time he'll know who allows him to be with you."
If you had known then what you knew now, you would have stopped seeing him after that first time.
But you didn't know; so you didn't stop...