Papyrus knows he shouldn't be doing this. This was wrong. Even if this was a world full of sex, it was wrong to fuck your brother without consent. Of course papyrus loved mettaton with all his heart. He would never touch him until he was ready and that would take a long time. Papyrus said he would wait. But his instincts didn't. His lust was unbearable to control. The royal harem was okay to say the least to satisfy his needs. But it wasn't enough. So he had to turn to the one person he knew would. His brother.

His brother, sans, was known to be a hot shot in the underground and known for being the biggest slut in all of Snowdin. Undyne insisted he should join the royal harem, but he refused. Sans wanted his brother to have the spotlight. Papyrus was lucky to have a brother like sans. He even brought food and enough money to keep them safe and warm. He knew that when they first moved to Snowdin, they had nothing. No one would help them, sans grew desperate as he wanted to feed his little bro. It was then sans turned to prostitution. As much sans hated the option, it at least gave him what they needed. And he was happy it made papyrus happy.

As years past sans became consumed of the lust. So much he became obsessed. So much Papyrus constantly saw other monsters entering his house. More than he can count. He knows he wasn't jealous, but he hated the way he could hear those other monsters with his brother on the other side of the wall in his room. The way they called his brother. It was so vulgar. He hated it so much. Which is why papyrus wanted sans to take his virginity first.

"You want to what bro?"

"I want to understand what sex is. I want you to be my first." Sans paused at this. Sans never wanted him to be corrupted to the lust of sex. The craving. The obsession. But papyrus was 13 entering the stage of hormones. It was papyrus' decision to have his first time. And sans had no say in it. If papyrus wanted him to be his first...then so be it. "Will I hurt you?" Papyrus's voice shaking. They've gone so far in this. So much that papyrus was about to enter his brother. Sans positioned himself at the right angle. As papyrus said that sans chuckled.

"Only if you're gentle~ but it's okay you're my baby bro~" sans slammed down. Sans clenched tightly around papyrus as he groaned. Papyrus gasped as he was engulfed by the hot slick walls that spasms around him. Sans them flips so that papyrus was on top. "So go all out~" sans's cheek bone began to flush as the member of his brother was already hitting a pleasure spot. Papyrus could take the pleasure as he began to move. It was so warm. He moved slowly as he wanted to savor the feeling of this pleasure. This was his first time after all. Sans was smaller than him, as each thrust he took, he felt like was being pummeled into the mattress. It was then papyrus began to speed up, already used to the slickness of the moist cavern. Sans tried to widen his legs as he tried to suck in more of the member impaling him.

Papyrus then shoved them farther than sans though he would, hammering inside him.

"AHH! Paps! That's too MUCH!" Papyrus didn't listen as lifted his hipbones to clack together. Sans's walls were constricting around him. Papyrus groaned as he came inside his brother. Sans gasped loudly as the hot fluid shot in too soon. Sans came with scream as he clamped down. Papyrus kept going. Getting so lost in the pleasure. As his cunt was abused so harshly, sans knew what was happening. He was corrupting his brother. Corrupting his brother into the same lust he was obsessed with now. And sans hated himself for that.

Ever since that day papyrus became desperate for sex just as sans was. Everyone here was. Every single monster was obsessed with sex. All except mettaton. The one papyrus loved dearly with all his heart. All but wondering, was mettaton really? I mean of course he was. Right?

Ever since papyrus and mettaton began to be close to having sex, sans stopped having sex with him for awhile. Sans was of course happy that his brother finally met theone he would love. But papyrus still felt empty. Everything in his life was full because his brother was in it. But it's empty now. Sex was the only interaction papyrus had with his brother. Besides living together. But he knows that sans will stop having sex with him completely. Besides, sans said he was going to move in with Grillby. Grillby was lucky to have a monster like sans. Sans was the best thing Grillby had and sans with mutual feelings. This made papyrus wonder. What was it like? What was it like to be loved. Not just by anyone but by sans specifically. Not by just sex, but with real love. More than brotherly.

Papyrus wanted that too. But what he was doing was wrong. But he didn't care. He wanted to be loved too.

Sans gasped in his sleep as he was being fingered brutally in his cunt. Papyrus watched his brother's expression. His pleasure. Looking at him now, it made him more cute. Papyrus wanted his brother so bad. He wasn't sure if it was his lust, or his heart speaking. But he didn't care. All he wanted was relief.

"Sans. Brother. I hope you don't mind if me using you. You won't mind right? Know you won't. I'm you little brother. You let me do what even I want. Even with you."

Sans was knocked out as his he was breathing heavily. He clenched the pillows as his cunt was stretched fully.

"Look at you brother.~ you're all slick and tight for me. Every time I stretch you out, you clench back in. I know you'll hold my sperm well~" sans's sleepy reflexes kicked in as he tried to move away from the pleasure. Papyrus saw this as he held him in place. "Don't try to hide away the pleasure brother~ I know you want this as much as I do." Sans squirmed in his sleep as he felt his pleasure rising. "It looks like you're about to come, go ahead. I won't stop you." Papyrus roughly shoves his finger in the tight walls. Sans whimpers as he comes around the long fingers. Papyrus pulls out his fingers, already missing the way his brother clenched around them.

Sans's body felt like it was over as sans went back to his peaceful sleep. Papyrus smirked at this as they were far from done. Papyrus began to pull down his pajama pants to reveal his erect member. He began to stroke it as beads of cum began to dribble down. He began to line himself up. Once he was in the right position he began to be sucked in the tight walls he remembers. His first time. It felt marvelous. Sans's walls weren't used to the thickness of papyrus's cock. It seems like he hasn't had sex for a while. As papyrus pushed his way in, sans whimpered. Papyrus stares at his brother. He looks like he's having his first time. So cute.

He slowly slides out as the walls begin to shudder in anticipation. Sans sucks in an unneeded breathe. He clenches the pillows as his walls clench around papyrus's cock. The unexpected response had papyrus's arms give out on him and just groan in the pleasure. But he couldn't stop there. Not when he wanted relief so badly.

"Shit, brother. You're squeezing me so tight, I can barely hold on much longer." It was then papyrus began a slow rough pace. Sans gave out soft groans and moans. This irritated papyrus as he wanted to hear loud gasps and squeals of bliss. Papyrus gave out more harsher thrusts as he was begging, forcing more lovable cries of pleasure. Sans's voice began to rise higher as he being pushed to his limits of another orgasm. His entrance twitching and begging for release to return back to it's state of the afterglow of it's last orgasm. Papyrus knows he shouldn't be doing this, but he can't help it. it was so addicting. Too addicting. Sans was his brother for Asgore's sake! But the way he's doing this to sans, who is ASLEEP. It just makes him think they aren't brother. Which encourages him to continue. He knows it's a guilty pleasure he should be ashamed of, but for now, right now..."Let's not be brothers for tonight sans.~" papyrus whispers quietly as sans was still surprisingly asleep through all of this. It was when sans gave the most pleasurable noises he loved. Sans gave out a squeal as papyrus found the perfect spot to get what he wanted. It was then sans clenched hard around his member. Papyrus sucked in a breathe as he noticed sans was already destroying his pillows.

"G-Grilllbbby~!" Papyrus stopped at this. Papyrus tried not to let out a sob as sans was continuously shouting Grillby's name. Of course the fire element would be in his brother's fantasies. Papyrus was nothing more than his little brother. papyrus's tears fell as he was thrusting into his brother harder. sans never stopped yelling that name. "Grillby! Grillby! oh stars-! GRILLBY!" papyrus doesn't want to hear it. he wants to hear his own name. Papyrus was being hurt by that name and he wanted sans to STOP.

'please...don't say that name. I want you to say my name.'

sans gave out his last orgasm as he came around papyrus. Yelling that name that finally made papyrus sob.

"GRILLBY~! CUMMING-!"

papyrus finally gave into his orgasm as he heard his brother say that name he now envied. HATED. as they came, sans began to fall back to his peaceful slumber. Papyrus though? He cried. he cried as his sleeping brother was fantasizing of another. while they fucked. he felt so unloved. unwanted in his brother's life. He knows that he would never be selfish. But can he at least be selfish just this once? He could have his brother all to himself. Have the love he wants. Needs. All the other papyruses have their sanses, so why can't he? What made him different? It was obvious that he already knew that answer. He was part of an AU where sans would fall for Grillby. Papyrus want to know how it was like being love by sans. How did it feel? He wants to kiss sans too. Not just because of the lust, but with his love. His true love. It would be a glorious feeling. Even more than just the sex. He then slowly pulled out of sans as his cum stopped flowing.

With his legs wobbly, he tucked sans back in and left to his room to sleep. As he now laid in his bed, he knew that his greedy and needy feelings for his brother was his dirty little secret. His and his alone. Sans might as well give up on Grillby, because he belongs to him. It would be fun, to be naive and have an adoration for a robot when it was his brother in secret. And without him knowing, he would indulge in his most guiltiest pleasure in his big brother's own sleep. They wouldn't know what hit em'. And if anyone ever found out. He'll make sure they go out with a bang.

"Brother! you're awake! Finally! I was about to storm in your room to wake you." papyrus yelled from the kitchen as he looked to he his brother finally up and down stairs.

"Heh. Yep. Ya know me bro." sans mumbled as he sat down on the couch. he slouched as slumber was taking control of his body once more. It was then papyrus came and sat a plate of his famous spaghetti on his lap. Even though papyrus's cooking was...mediocre, sans as always and lovingly swallowed his gut (heh) and gobbled it all down. It was then papyrus began to feel fidgety. he oblivious older brother unaware that there was evidence of their love making only papyrus knew.

"So...dear brother...how did you sleep last night?" sans slurped up the noodles of spaghetti before responding.

"Mm...same old, same old bro. But if I had to be honest, it was the best sleep I've had, or should I say WET dream." sans said in a suggestive way as he rubbed his femurs together, to feel the same friction when he was in his deep slumber. his arousal was seeping a bit through his short, shorts. Papyrus watched with arousal in his eyelights as he saw well he drove his brother up a wall last night. It was then stared up at his brother. he then put his plate of spaghetti on the coffee table.

"Maybe you can make it better?~" sans whispered as he climbed in his lap. Papyrus was shaking in delight. their teeth were dangerously close as sans's formed sex was just hovering above his pelvis. Papyrus could feel the heat radiating off the delicious opening. He would give anything to just rut into it. Feel it drip and ooze uncontrollably as his brother would be practically begging for his cock to fuck him. Make him loose control in delight. Scream at the top of his lungs and chant his name like a mantra. They were so close. So close that-

"Of course I have grillbz, and you have Mettaton for relief. I shouldn't break that. We're all pals here." sans said as he gradually got off his lap and went back to eating his spaghetti. Oh man, papyrus wished they would just enjoy their desires for just a while. Of course one round with other monsters were just a one time thing, but when it came to his brother, one round just wasn't enough. Sans then got up with his plate and took it to the sink.

"Well, paps, breakfast was real nice, but I have work to go to. Those cocks aren't going to suck themselves! Well...I guess they could~" sans was so smitten. It was then sans was gone in a flash. Papyrus knows that sans is going to go to Grillby's first. It's where most monsters know where to have the cheapest round with sans. Anywhere else, the price was raised. There were so many monsters there waiting for a turn to fuck his brother, there were times where sans wouldn't come home for a day and a half. And when that happened, Grillby would bring back a worn out, overstimulated and pleasured skeleton. Papyrus knows that sex the one thing that gave them the most money, but papyrus wanted his brother here with him. At home. But as the same for him and others, just one round with sans just wasn't enough. They were all greedy. Obsessed even. So obsessed of the lust that they put sans on a pedestal of it all. Even the king and queen had a lust for his brother as well. Sometimes they would request of his brother just for sex and would pay extra for his salary.

But of course sans would have on passion of love just one monster in the whole underground. Sans should have chose papyrus. Sans should have been his, but he went over to choose that pathetic fire element and he was too oblivious to realize sans was his all along. But papyrus was respectful towards Grillby because sans chose him fair and square. It would also break his big brother's heart to see the two people he loved be at each other's throats.

He shouldn't think about this too much. Mettaton should be coming over soon. Then he would try his efforts to get into the royal harem. Spend more time with meattaton. And then, only then after that he would be able to enjoy his guilty pleasures in the dead of night. This was a big turn of events in his smitten pleasures. As he thought this he began to laugh to himself at how much fun this would be.

"Oh sans. I'm sure my name will be the only name you'll be screaming. I'll make sure of it~"

FIN