[Author's Note: I will look over suggestions, I'm very excited to see where this story goes, and your suggestions make it all the better! Also I make short chapters and ship Franks, deal with it? 3]
Frisk awoke with sans still running his fingers through their hair. Had he been doing that all night? Frisk's stomach ached but hasn't thrown up since they took the medicine. They actually almost felt completely better, maybe it was just a 24 hour stomach bug. Frisk forced their eyes open and stretched their arms and back, making bones pop in several places. Sans flinched.
"mornin'. you really gave me a scare last night, pal. You seemed perfectly okay walking to grillbz. then all of a sudden you started shaking and gross stuff started coming out of your mouth. it smelled terrible to be honest. how are you feeling now?" sans got up from his chair and sat on the edge of the bed. He put his hands up to Frisk's forehead and felt its normal temperature. He let out a silent sigh of relief. "so what the hell happened?" sans asked looking at Frisk.
Frisk shrugged in response, "a lot of times humans get sick and don't know why. But it could be because of all the excitement of breaking the barrier, or it could just be a 24 hour stomach bug" sans tilted his head at that.
"you have bugs in your stomach?" sans asked confused. Frisk shook their head and chuckled.
"It means you get a virus for a short time and then it goes away. Humans can recover pretty fast" Frisk smiled and sat up "but at least I'm all better for the party today! You'll be there right?" Frisk looked up at sans expectantly, sans was avoiding their eyes and looked at the wall on the other side of the room.
"i dunno, kid. i have a lot i need to get done. i'm in the middle of something really important, the brink of a breakthrough, let me tell ya. it'll help us understand time better, help me find some answers i've been searching years for. i'll probably stop by later tonight, but not for long" sans saw the excitement drain from their eyes. shit. they were looking forward to me being there. but i don't know if i can handle being around so many people. i'm so fucking tired, what if i… on accident…? no, he wouldn't. that's why he wouldn't be there for long. Frisk doesn't understand why, but sans can't be around Frisk right now, or anyone for that matter. it's for their own protection, he thought.
There was a soft knock on sans' door, Papyrus called on the other side "BROTHER, MAY I COME IN, I WISH TO CHECK ON MY DEAR FRIEND" sans hopped off the bed and opened the door, Papyrus walked inside and sat on the bed. "FRISK YOU ARE LOOKING WELL! I'M SO RELIEVED TO SEE YOU IN GOOD HEALTH! TORIEL WILL BE OVER IN A MINUTE TO TAKE YOU HOME, BUT I WILL SEE YOU AT THE PARTY TONIGHT IF YOU ARE STILL NOT ILL!" Papyrus gave frisk a hug and patted them on the head, Frisk smiled hearing the news of Papyrus attending their party. "I MUST READY MYSELF, I AM GOING TO BRING A MEAL FOR DINNER, IT IS A SURPRISE SO DO NOT GO IN THE KITCHEN!" Papyrus got up and left the room. He called from downstairs "FRISK, TORIEL IS HERE!"
Frisk jumped off the bed and realized they were still wearing sans' jacket. It was a heavier coat lined with soft fuzzy fur on the inside, it reminded Frisk of Toriel's warm furry hugs. Frisk unzipped it and handed it to sans. "ya sure, kid? you don't wanna just borrow it for the day?" Frisk grinned and quickly zipped the jacket back up. Frisk gave sans a hug, and held it for a while.
"Thanks for taking care of me" Frisk said and put their forehead up against sans' and nuzzled it. sans looked down at the floor then up at the ceiling, avoiding Frisk's gaze.
"anytime, kid. y'know, i wouldn't be mad if you jumped to your last save if you died. i couldn't live without cha" sans was scratching the back of his head, there was a shadow cast across the bridge of his nose that spread to his cheeks, it looked almost...blue? "anyways, you go have fun, i'll see ya later tonight"
Frisk walked out of sans' room leaving him to sit and drown in his thoughts. He had too much on his mind, he had to do something to occupy it. He had to figure out that damn machine downstairs. Sans walked to the back left corner of his room and took a step through a shortcut into his lab back in snowdin. He tore off the sheet and what stood before him was a large cylindrical machine with a screen and a keyboard that had strange symbols on it. The screen was on but showed nothing but static. There was a loud humming coming from the machine, sans picked up some papers that were scrambled about the counter next to the machine, he matched the symbols in the notes to the symbols on the keys, shuffling through the papers, reading the strange symbols as if it was a second language to him, because it was.
Something in the machine clicked and hissed, sans looked up at the screen, it twitched, but was still static, but it sounded like he could hear…. voices? coming from inside? He furiously typed in more strings of symbols and the screen turned black, it looked like it shut off.
"what? no.. no no fuck what did i do? gaster? can you hear me?" he pounded on the machine, the screen flashed a face. It was white with cracks in the skull. It was Gaster, but not as sans remembered him. The picture appeared corrupted, the pixels were distorted and the next second the face was gone. sans gaped at the screen and quickly scribbled the order of the symbols he typed in. "okay… okay progress. i'll getcha back, don't worry."
Meanwhile Frisk was dressed up for the party, they wore a long black turtleneck sweater that had a white stripe in the center. It was long enough to look like a dress, Frisk wore leggings and boots along with it.
The house was spotless and smelled of pie, as always. There were several wooden chairs set up in the living room and kitchen for the guests to sit. There was some music playing from the stereo, it was a happy but familiar tune that Frisk couldn't quite place. There was some Mettaton show on the TV.
Papyrus was the first to arrive, he brought the smell of noodles and sauce with him. In a glass pan sat a huge lasagna. It looked like the edges were burnt but the rest of it looked pretty good.
"DO NOT WORRY TORIEL I HAVE BROUGHT THE GIFT OF LASAGNA! IT IS A SPAGHETTI CAKE! OR, ER, A SPAGHETTI CASSEROLE, PERHAPS? NONE THE LESS IT IS SPAGHETTI, AND IT IS EVEN BETTER BECAUSE I, THE GREAT PAPYRUS, MADE IT!" Toriel thanked him and grabbed the plate and put it in the kitchen with the rest of the snacks.
Undyne and Alphys were the next to arrive, Alphys held the door open for Undyne to prevent her from breaking another. Undyne walked through the house smirking and nodding approvingly at the house, "Not too shabby, homey as always" she said to Asgore as he came out of his room. Him and Undyne sat on the couch and talked, laughing, Alphys was standing next to Undyne with her face in her phone tapping away.
Mettaton even managed to drop by and say hello to Alphys, congratulate Asgore and Toriel and to thank Frisk. It seemed all of Ebott showed up to the party, Woshua was in the kitchen cleaning dishes, Napstablook took over the stereo and was playing some of their own music. It was a happy day. Everyone was content and laughing, talking among one another, eating, and dancing. The party was a huge success.
It must have been after midnight before the party finally died down and guests began to leave. Papyrus generously left the rest of the lasagna in the fridge for Frisk the following day. sans never did show up. Frisk was a little disappointed but knew sans was not feeling quite himself, they only hoped sans was finally sleeping. The shadows under his eyes were worrying Frisk, and he wasn't throwing jokes around like he usually did. Frisk said goodnight to Toriel and Asgore when everyone had left, gave them each a big hug and went to their room. They laid in their bed and cuddled further into sans' jacket. They supposed they would be keeping it safe tonight since sans didn't show up. It smelled good, it smelled like...safety? Protection? but also good, like a cooler smell before it rained. Frisk fell asleep with the smell surrounding their thoughts.