Here's a YCH comm I just got from https://twitter.com/COMICFIRUKO! The first YCH I ever bought! In this pic (and accompanying story), Jam ran afoul of Santa by switching out some chocolate chip cookies for sugar-free ones! As you can tell, Santa does not take this well. Was originally going to include more characters in this story, but I wanted to mainly focus on Jam and Peppermint with a cameo by Santa. I feel Christmas stories work better when they're smaller and self-contained! Also, contains a cameo mention of  Mallardent's Felgar!

Story:

It was the night before Christmas and all was well in Jam's lab, at least for the time being. Things usually get nuts on any day of the week and Christmas was no exception. Peppermint the robo-moth had just finished decorating Jam's lab for the season. Lights were hung up all around the lab and there was a large tree in the middle. Next to said tree was a tray of cookies with a note attached to it that read, "To Santa!"


Peppermint beeped happily as she put the star at the top of the tree. The green-and-pink metallic moth stepped back and admired her handiwork, "Perfect! I'm really glad dad programmed me with all these decorating protocols!"


Peppermint's dad, Jam, entered the room just as she was finishing up. The monkey-scientist stood at 3 feet tall and had a long prehensile tail, shaggy brown fur, and hands for feet. Jam looked at the moth, "What'cha doing?"


Peppermint giggled in a robotic-sounding voice, "Getting the house set up for Santa, of course!"


"Oh, neat!"


Peppermint looked down at the monkey in confusion, "Huh, I was expecting you to say something like 'Santa isn't real'!"


"Why would I say that?"


"Because you're a scientist,"


Jam snickered, "Oh come on, I deal with magical entities all the time! My arch-rival is a demon duck named 'Felgar', remember?"


"Fair point!"


"Besides, it's not that I don't believe in him, just never met the guy. I've never written to him, nor had reasons to write to him! As such, he's never once visited this lab. Maybe he exists, maybe he doesn't. Guess I'll never know,"


Peppermint gave Jam a digital wink, "Well, if he exists then we'll find out tonight!"


"You wrote to him?"


"Yep!"


"What did you ask for?"


"Proof that he exists!"


Jam rubbed his finger against his chin and smiled, "Oh, that's genius! So, if he comes and eats the cookies, he 'delivers your gift' by proving his existence,"


Peppermint nodded, "And if he doesn't eat them, it proves he's fake and we get to keep the cookies!"



Jam stood on his hands and clapped his hand-feet together, "This is a great experiment! I can't wait to see how this plays out,"


Peppermint stretched her metallic arms, "Me too! I'm heading to bed though! Night, dad, and don't touch the cookies!"


Jam smiled innocently and crossed his finger-toes, "Me? I wouldn't do such a thing!"


Peppermint sighed, "I find that hard to believe, but we'll find out tomorrow regardless!"


Peppermint marched off to her charging station, right before plugging herself in and instantly losing consciousness. With Peppermint asleep, Jam cackled mischievously to himself. He grabbed the plate of chocolate-chip cookies and stashed them in a nearby cupboard. He then placed a plate of sugar-free cookies in their place. Jam laughed maniacally while committing this fiendish act, "If Santa is real, he can go on a diet!"


Jam then walked over to his hammock and leapt onto it, quickly falling asleep in the process. Hours passed and a large sleigh pulled by reindeer landed quietly atop the ceiling of Jam's lab. Santa Claus noticed there was no chimney on Jam's roof, but that never stopped him before! Santa clapped his gloved hands together, causing a chimney to magically appear on Jam's roof. Santa slid down the chimney and into the lab of the monkey-scientist.


He held his heavy sack of presents tightly as he walked over to the nearby plate of cookies. Santa couldn't resist the sight of sweet, sugary confections! As he approached, he felt something was off. He looked down at the cookies and using his keen "Santa-Sense", was able to notice that none of the cookies had sugar in them.


He quietly gasped, "That cheeky monkey, he switched out the cookies! Nobody tells Santa to watch his weight!"


The jolly fat man turned his attention to the sleeping monkey and began to quietly tip-toe towards the hammock. He wiggled his gloved fingers around and shot some magic at the sleeping monkey, "We'll see who needs to go on a diet now!"


Jam didn't notice any of this and continued to sleep, unaware of the strange change he was currently undergoing. After Santa did his work, he tracked down the actual cookies, ate them, and left. Several hours passed and Peppermint woke up, unplugging herself from her charging station. She wandered back to the plate of cookies and noticed that they were still there.


Peppermint hung her head in shame, "Darn it! There goes that scientific endeavor! Wait..."


As Peppermint looked at the cookies, she noticed something was off. She scanned them using her digital display and noticed that they didn't contain any sugar or chocolate chips whatsoever. Peppermint instantly knew what was up, "That greedy chimp switched out the cookies!"


Peppermint marched into the room where Jam's hammock was and noticed a strange sight! Jam's hammock was broken and lying on the ground, but he was nowhere to be seen. Instead, a being who appeared to be Santa was seated atop the broken hammock. He matched Peppermint's data log on him: He had the red suit, matching red hat, the extremely fat build, the brown boots, the green gloves, and the black belt!


"Santa" was sleeping on the ground with his back facing Peppermint. She was afraid that Jam was underneath the slumbering jolly giant! She rant up to the jolly fat man and poked his back, "Santa, get up! Get off my dad!"


The fat man woke up and yawned, "What? Peppermint?"


He turned and revealed himself to Peppermint, causing her to laugh like crazy! The man wasn't Santa at all, but an incredibly fat Jam in a Santa suit! Jam was now twice the height he once was, his body now full of flab. His arms and legs were as chunky as slabs of meat, his stomach as big as a beachball.


Jam hobbled onto his pudgy legs, causing his fat stomach to jiggle around like a bowl fully of jelly, "What's so funny?"


Peppermint snickered, "Look down, dad!"


Jam looked down and was met with a massive belly, one that was so big he couldn't see his own legs! He held his bulbous hands in front of his face and saw they were covered in thick green gloves! Jam could deal with being really fat, but wearing this much clothes went against his monkey mantra of natural nudeness, "I hate this!"


He reached his hands down and grabbed the sides of his belt, trying his best to wriggle it off so he could remove his suit, but it was to no avail! He struggled and grunted for several minutes to get the suit off, Peppermint laughing at him as he attempted to do so. After several minutes of trying, he gave up.


Jam sighed as he crossed his chunky arms, "I can't believe that jolly fat man did this to me!"


"Jam, you brought this on yourself! You're the one who switched out Santa's cookies with sugar-free ones,"


Jam scoffed, "Oh, excuse me for trying to put Santa on a diet!"


Peppermint giggled and poked Jam's belly, "Looks like you're the one who has to go on a diet now!"


Jam grumbled as his big belly jiggled around from the poke, "Ha ha, very funny!"


Peppermint tilted her head, "Say, where did you put the cookies you took? I know you're not the kind of guy who would scarf a plate full of cookies in one night, even though you look like you easily could now!"


The monkey nodded, "Uh... Yeah, I could show you where they are! I don't know how that could help my current situation though,"


Jam then took a single step and quickly lost his breath. He began to sweat profusely, while also panting uncontrollably. His much fatter body was so out of shape that even the smallest movement could tire him out, much to his dismay. Peppermint walked over to the fattened monkey, "Maybe you could just tell me where it is and I could go get it?"


Jam nodded and wiped the sweat off his forehead, "Go ahead! It's in the cupboard,"


Peppermint walked over to the cupboard and opened it, peering inside for the plate. She grabbed it and noticed that all the cookies had been eaten, with the only thing left behind being a note. Peppermint let out a satisfied beep as she grabbed the empty plate, "Ah, just as I predicted!"


Jam scratched his flabby butt in confusion, "What?"


Peppermint carried the plate over to Jam, "Santa left a note!"


"How did you know that?"


"I remember reading in my Santa lore that he sometimes leaves notes behind. I also figured that since he didn't touch the sugar-free cookies at all, he must've gone for the actual cookies. And being magic, he'd be able to easily detect them!"


"Makes sense, I guess. Anyway, let's read that note,"


Jam grabbed the note and read it out loud: "Dear Jam, I didn't appreciate you trying to stiff me with sugar-free cookies. A jolly fat man like me needs to keep his flabby figure. I figured you'd like a sample of what it's like to be me, so I gave you my weight class and a copy of my outfit! You'll return to normal the day before New Years. Enjoy, fatass! Signed, Santa Claus,"


Jam angrily crumpled the note, "Man, Santa's kind of a dick!"


Peppermint giggled and beeped, "To be fair, I'm sure you're on the Naughty List! You probably had this coming for a long while,"


Jam grumbled and put his hands on his chunky hips, "Weird that you'd take Santa's side and not your own father's!"


"To be fair, the line between you and Santa is kind of blurred right now!"


Jam sighed, "I guess you're right there!"


"And at least we proved Santa was real, so there's a win right there,"


"True! Now, how we about we celebrate Christmas my way and go play some Phantasy Star Online on the Gamecube?"


"You read my mind, pops!"


The two then proceeded to walk towards the living room, with Jam needing to take repeat breaks due to his out-of-shape form. Before they could reach the living room, Jam spotted the plate of sugar-free cookies. A ravenous hunger quickly brewed within Jam, prompting him to grab the plate and dump all the cookies into his big fat maw.


After eating all the cookies, Jam grumbled and placed the empty plate back on the table, "Dang it! Santa gave me his massive appetite too!"


Peppermint playfully petted the monkey's head, "Look on the bright side!"


"And what's that?"


"At least those cookies were sugar-free!"


The father-and-daughter duo shared a good laugh at Peppermint's jab and walked off to enjoy their Christmas day. Jam learned that day to never get between Santa and sugary confections. After all, a fat man needs his cookies!