Work Text:
Toriel had been teaching Papyrus (and in turn, Undyne) how to cook properly as well as cooking meals other than spaghetti. While Papyrus learn to make edible things, Toriel made food exclusively for Frisk to avoid them getting sick. If she, as a monster, couldn’t handle Papyrus’ creations, it wasn’t fit for human consumption. Sans remained as the guinea pig for anything Papyrus made. Sans never admitted to his brother directly that his cooking was terrible, but with Toriel un-teaching Undyne’s lessons, Papyrus was actually improving.
“Here, Sans, my dear brother try this!” Papyrus announced as he shoved a plate of pasta in front of Sans’s vision.
“Kinda busy, bro. I’m playing a game here.” Sans didn’t take his eye sockets off the TV.
“Just pause it or let Frisk win, this is important!” Papyrus stamped his foot impatiently.
“Alright, alright.” Sans sighed.
He put the wii remote down and let his telekinesis take over the button mashing against Frisk in ‘Brawl’. He quickly glanced at the plate sitting on his lap and it looked alright. One bite and he could have sworn it was Toriel’s cooking...just a little overdone.
“Whoa, Papyrus! This is really good! Best work yet.” He grinned up at his brother slurping down an impolite amount of pasta.
“Wonderful!” Papyrus beamed, “I knew those tediously calm lessons with Miss Toriel would pay off!”
It was only a small portion so Sans finished his plate quickly.
“Thanks for that, bro.”
“Would you like some more?” Papyrus asked, taking the plate and fork away.
“Later, thanks.” And he resumed his game with Frisk.
~
When Sans said ‘later’, he meant tomorrow. Not when he was about to go to bed. Papyrus ushered him into the kitchen where a small banquet of pasta awaited him.
“You have to try everything!” Papyrus grinned, struggling to keep his excited voice low as everyone else should be in bed.
“You serious Papyrus?” seeing the look on his brother's face answered that question, “Well, alright. Just one bite of each?”
“You liked my other spaghetti so much, you gotta try each whole dish.”
Because I was hungry then, Sans didn’t say. He sat down and hoped he had room in his non visible stomach for all of this. He refused to count how many plates and bowls of pasta there was and focused on each meal as it came to him. Sans was used to pigging out on junk food in his spare time but not with someone hovering over him so eagerly watching his every fork movement.
One plate down, two, three... Papyrus requested feedback after every finished dish. Sans layered him with compliments. It was a good chance to pause from eating and attempt to digest. Papyrus was jumping for joy to substitute his usual loud voice and kept thanking his brother over and over for the praise.
Four plates down and Sans was getting uncomfortably full. Toriel’s dinner plus dessert was barely 3 hours behind him so Sans didn’t exactly start with an empty stomach. His PJs matched the outward curve of his once invisible stomach. It was now turning blue as it flushed to match the colour of his powers. Papyrus didn’t seem to notice the growing discontent on Sans’ midsection and slid another bowl of pasta in front of him.
Sans carried on eating, a little slower now. He started yawning in hopes Papyrus would recognise he was too tired to continue and let him go to bed. He didn’t want to be rude and ask to stop, Papyrus would only complain and then they’d both feel bad.
So he pushed onwards, shoving more pasta, meatballs, cheese and sauce through his mouth while ignoring the tightening feeling in his midsection...and lower. He didn’t have to feel ashamed around Papyrus; he had caught him out gorged out on a hot box full of leftover hot dogs and just carried him to bed. But right now he just wanted to slip a hand down and give himself a well needed tummy rub without making it look lewd to Papyrus.
Another plate finished and Sans started up his compliments again when a loud gurgle emitted from his stomach.
“Oh brother, are you alright?” Papyrus asked, his eyes looking directly at his obviously round belly.
“Y-yeah, just a bit full that’s all.” Sans grinned weakly up at him.
Sans tried to rub at his belly but found it pushing against the table. He pulled his chair back a bit and unashamedly rubbed the section that had been wedged against the table. His top was useless at covering his belly now so his glowing blue stomach was hanging out for display.
“Oh dear, maybe I did make too many samples.” Papyrus wrung his apron anxiously.
“Nah it’s all good what’s left...” Sans braved a look at the table and saw mostly empty plates besides one large bowl.
“Do you really think you can finish it? I don’t want you to get hurt and burst something.”
“I’ll handle it. See? There’s still room in me.” Sans lifted his shirt more and showed off the swirling mass of pasta visible in his blue belly.
“Ugh, Sans, have some decency.” Papyrus looked sick.
Sans struggled to pull his top back down and started on the last bowl of pasta. He leaned back in his chair with the bowl resting on his soft belly and ate it whilst paying no attention to Papyrus. Letting his guard down was a bad idea because suddenly he felt warm bones creeping up his sides. Sans looked over his bowl of pasta and could just see over his belly at Papyrus on his knees.
“W-what are you doing, bro?” Sans’ voice shook, getting the wrong idea.
“You look like you need some relief, so I, the great Papyrus will give you tummy rubs.” Papyrus said almost in his usual voice level in his enthusiasm.
“Heh, thanks Papyrus.” Sans smirked.
Both were content for the next few minutes. Sans slowly finishing off the pasta despite his belly straining and protesting while Papyrus gave him soft tummy rubs to ease any cramps. If anyone walked in the kitchen right now for a midnight glass of water they’d have a lot of explaining to do.
Finally Sans finished up the last of the pasta and heaved a sigh of relief, making his belly expand even more with the influx of oxygen. The blue of his stomach was faded due to stretching so much and all of its contents where pressing against the clear sides. Anything more and he would be on the verge of bursting.
“Well, Papyrus, your cooking has definitely improved. I do have some advice though.”
“Yes, Sans?”
“When you cook for anyone other than me, remember not to cook so much.” Sans let out a laugh but soon regretted it as it made his whole belly shake.
“True, you are a glutton. Thank you for trying my cooking, Sans. Let me help you one more time.” Papyrus smiled gently.
He scooped Sans up into his arms with only minor difficulty and carried him up to his room. Sans practically rolled into bed and fell into a food coma. Papyrus pulled the sheets over him and put his face to Sans in attempt of a lip-less kiss.