Sometimes it was just amazing how much the crazyist stuff in Marinette's life didn't happen to her while she was the teenaged hero of Paris Ladybug..but more when she was just her normal old self.
Case and point? at the moment the teenager was currently dressed in a massive thick cloth diaper with a over sides safety pin keeping it closed snug around her hips. 
Add on to THAT a cream white top with a cartoony sun on the front and a caption under it reading 'mommies little sun shrine.'
The shirt was almost too tight to get on and was much too short for Marinette's normal tastes, coming up just under her budding breasts. 
the one thing that Marinette had been allowed to decide on her own for her current attire by the strict taskmaster in charge was whether or not to wear a large baby bonnet that was yellow with white frills or have her hair brushed into pig tails. 
Since her taskmaster was the 6 year old Manon who wasn't always that gentle brushing her doll's hair Marinette had opted for the baby bonnet and so it was fastened in place with a large bow that had been tied with a not.
'I don't even wanna THINK about how I'm gonna get this off later.' Marinette thought gloomily but kept a smile on her face. 
"Does mommies little girl want a ba-ba?" Manon asked, offering Marinette a baby bottle with what MIGHT of once of been milk floating in it.
"Er..Mommy." Marinette started, trying to pick her words carefully. 
Manon was a well know popular target for being akumaized by the villain Hawkmoth and Ladybug was trying NOT to trigger a attack. "I would love one but I think that milk's gone off. you don't wanna have a baby with a icky tum tum do you?" she asked.
Manon looked like she had been about to get mad, then looked at the bottle and giggled, doing a light forehead slap. 
"oh! Hehe, Good catch! Thanks Marinette! your the best babysitter ever!" the little girl said then added with a evil little giggle. "and a even better baby!" before dashing off to the kitchen to go and wash the bottle out and refill it. 
"..How can she be so cute and funny and so evil at the same time?" Marinette grumbled.
it was her own fault though in a way that she was currently playing house as the baby, since having to rush over for the babysitting job when Rose had been forced to cancel she hadn't been thinking when she promised to play whatever game Manon wanted when the 6 year old had asked.
and since breaking a promise with her was a good way to bring back The puppeteer...Marinette would just have to suffer till the kid got sick of playing house.
'Which hopefully happened before I end up needing a diaper change.' Marinette thought with a small giggle. 
she didn't see herself actually having to use the diaper but it WAS funny (if not a little mortifying ) to mentally picture.
"What's so funny?" Manon asked as she came back, a clean bottle filled with cold milk in hand.
"Oh, nothing much man..Mommy. Just silly baby thoughts." Marinette said.
"heh, well let's get your ba-ba in you and then you can giggle and wet yourself to your hearts content! I got LOTS of spare diapers!" Manon said, grinning big time. 
Knowing that asking why, or trying to insist she could feed herself would just upset the little lady, Marinette crawled over to were Manon had sat down and put her head in the smaller girls lap, opening her mouth.
'At least no one else is going to see this.' She thought with a blush as she started to nurse on the offered nipple.
Of course, temping fate like that was never a wise move, let alone if your a superhero.

Rose was rushing over to the Chamack's house, feeling both silly and awful as she went as fast as she could. 
After having to cancel babysitting and maybe ruining Mr. and Mrs. Chamck's romantic afternoon in the park because she had thought for sure she had a job interview today, she had realized only after getting to the coffee shop it was in fact for the next day. 
They hadn't phoned her back to let her know if they'd been able to find anther babysitter yet or not and so trying not to burn any bridges she was heading over to offer to sit or help the other sitter free of charge. 
Having become their go to weekend sitter Rose had her own key which she slide into the lock and started to open the door, knocking loudly on it as she came in. 
"Hello? It's me Rose! Turns out I could make it af-" She was in the middle of saying, when Manon burst out into the hallway from the living room and rushed over, giving her a BIG hug. 
"Rose! Rose! Rose! Your here!" She giggled excitedly.
"heh, Yup! where are your parents kiddo? did they manage to find you a babysitter?" Rose asked, not registering the evil little smile that came on the little girls face. 
"heh, they didn't find me a babysitter..but they did make sure I wasn't home alone.." Manon said.

Cards on the table, while Manon liked Marinette, it was more because she was SO easy to get to do whatever she wanted. like..what self respecting big girl would let herself be dressed like a big baby JUST to keep Manon from having a fit?! 
Rose on the other hand was a big girl that Manon respected and looked up to, and was trying to be a cool big sis like her for the dumb baby Marinette. 
"Huh? whats that suppose to mean?" Rose asked as she set Manon down on her feet. 
"Come on, I'll show you. Though head's up, this girl is a total liar and doesn't want anyone to know that she's being punished."  Manon said, making up a story on the spot. 
"oh? what's she being punished for, and whats the..pun..ishment..Marinette?!" Rose said, trailing off then yelping.
"R-Rose!?!" the big baby yelped.
"oh you know each other! that makes this MUCH easier." Manon said with a giggle. 

Marinette found herself wishing she had Cat noir's powers as she was being gawked at by a classmate in all her baby glory. she'd of used it to make a hole deep into the earth and just vanish. 
"heh, oh wow! I heard your parents had some weird ideas when it came to punishment..but making you be a big baby and get babysat? that's a new one!" Rose chuckled coming over and pulling a napkin out of her purse.
Before Marinette could even think of protesting her chin was being wiped as she had apparently spilled milk on it when Manon had jumped up and left her to bonk her head on the floor when she'd heard Rose calling hello. 
'Maybe that's it..I'm not actually being seen like this, I'm just all knocked silly!' Marinette thought, and had the briefest moment of blissful relief before realizing that was a pipe dream. 'Yeah.. and while I'm at it Kitty cat is the queen of England.' 
"O-Ok before this gets out of hand,. I think I should clear this up. I'm not being diaper punished or anything like that, me and Manon were just playing house and I was being the baby." Marinette said quickly, trying to pull away from the surprizingly strong Rose.
"See? what did I tell you? total liar liar diaper on fire." Manon said, shaking her head and waging a finger at Marinette. "Bad baby! lying will get your mouth washed out with soap if you don't stop!"
"W-what!?! but I'm no-" Marinette squeaked out, eyes going wide. 
"Now now little one, be a good girl. I don't wanna have to punish you, but Manon's right..little fibbers get their mouths washed out." Rose said and pulled back some, then patting Marinette's head. "and don't worry, I won't mention this to the rest of the class..at least as long as your a good little girl." Rose said and winked.
there it was..not only was Marinette heading for a bubble filled mouth if she kept trying to prove this was just a game, but now the threat of having rose tell every about how she was sporting diapers was hanging in the air. 
bottom lip trembling and looking up at Rose and Manon, Marinette said the only thing she could.
"Goo goo gaga."

Manon kept having to bite down on her tongue, this was just WAY too good! Not only had she gotten the best babysitter in rose, and had a big baby to play with..but Marinette had barely even bothered to try and put up a fight!
That if nothing else proved Manon was right that Marinette was nothing but a big baby and she had lots and lots of plans for a big baby wimp like her. 
'I wonder if I can get a stroller big enough to take her out to the park?" the 6 year old wondered.'Then again she might just try and bail if we take her outside..nothing to lose at that point.' 
In any case Manon sat back and watched the show as Rose tugged Marinette into her lap, a towel over one shoulder and started to burp the poor teenager, who went from whining that she could burp fine on her own to letting out a VERY unladylike belch. 
Seeing how red the so called big girl got, Manon just chuckled. 
'If she thinks it's bad now..wait till the laxative powder I put in her milk kicks in!' The little girl mentally cackled, proving you didn't have to be akumaized to be evil.

Rose just couldn't stop smiling as she snuggled and cuddled Marinette. before today she had never even thought about having a teenaged baby to tease and cuddle and look after ad now, well. 
'Never have I ever wanted something so much before!' 
She was going to have to totally try and see if she could be Marinette's punishment sitter, already making plans to call the big babies parents though a idea suddenly hit her and she paused from all the hugs and tickling she was doing, that had the helpless Marinette cooing and giggling like crazy.
"Oh uh..Baby Marinette, are those diapies just for show or.." She asked. 
"W-What!?" The mortified brunette squeaked out, though before she could say more Manon spoke up, being SUCH a good big 'sister' to the big baby.
"Oh yeah, she totally destroys them. we got lots of spares for when she makes 'presents'" Manon said, using her hands to make finger quotes.
"I-I DO NOT!" Marinette practically shrieked, going red as a tomato and squirming big time now in Rose's lap. "I use the potty like a big girl!"
"heh, If you call sitting on the training potty with your diapers on and going, then sure you do." Manon lied as Rose squealed.
"Oh my gosh! that sounds so adorable! Don't worry Marinette, Big sis rose will help you 'use the potty!'" Rose coo'ed, there was NO way she was going to miss seeing that.
"I..But..I.." Marinette stammered, whining and fussing. 
"Awww it's ok. You don't have to pretend you don't do it just because I'm here. our little secrete remember?" Rose promised and then started to tickle Marinette's exposed tummy.
which apparently kick started something before within 12 seconds of the tickling, Marinette went from helpless giggles and crying out 'stooopppp!' to a loud muffled fart escaping from her back door, freezing her. 
"Oh, Guess it's potty time sooner then I thought!" Rose laughed.

No matter how much Marinette tried to explain that she was a big girl, that she wanted to use the toilet like one, all that happened was Rose would say "of course" and keep leading the way to a large training potty shaped like a ducky and it even hand handles for the mortified hero to hold onto. 
Shooting a desperate look to Manon, Marinette's face it all, pleading with her to speak up and explain this was all just a game, to save her from being just a big stinky baby. 
unsurprisingly Manon just smirked and watched with delight as Marinette was sat down, poot after poot coming out and her tummy churning. 
Not helping things was it had been 2 days since she had last used the bathroom so not only was she about to fill a diaper for the amusement of two others..but it was gonna be a big one. 
'Wait thats it! That's how I can get out of this!' Marinette thought and smiled, then spoke out loud. "W-Wait! Rose! I-I haven't gone in a while..this is gonna be HUGE! you're NOT gonna wanna change the poopie diaper I-I'll make. I'm thinking of you now.. Please just let me use the potty and..and I swear next time I have to take a dump and I'm diapered I'll do it like a good girl!" Marinette said, laying on the baby charm.
"Hmmm.. I didn't really think about the clean up." Rose admitted and looked to Manon. "What do you think?"
A loud horrid smelling poot came out of Marinette, the muffling effect of the diapers negated by the ducky potty she was sitting on even if her massive diaper butt covered the hole. 
"Oh yuck!" Manon said and held her nose, looking unsure herself. 
"And that's anther thing! when I'm this backed up..it's TOXIC!" Marinette added, really warming up to her tune. "Trust me, between the size and the smell, this will be one diaper that you WON'T wanna change PLUS it'll earn me the title of stinkiest diaper girl in Paris!"
"..."
"..."
Manon and Rose looked at each other, then both smiled and nodded and turned back to Marinette who got a sinking feeling in her gut, and not just from the mess waiting to come out.
"Well shucks, now we HAVE to let you go in your diapers!" Manon said gleefully.
"Yeah, wouldn't be right to keep you from going for the gold! You can do it Marinette! we believe in you!" Rose said, pumping a fist in the air.
'..fuck my life..I'm a victim of my own PR.' Marinette mentally groaned and huffed out loud.
any futher complaint was cut off as with a final painful cramp, the number one hero in all of Paris griped the handles on the training potty and leaned forward, crying out as filled the seat of her diapers with a babyish cry of 
"I'M POOPING MY DIAPERS!!"

Manon was quickly and horribly seeing how her great evil plan to make Marinette a big helpless baby had a MAJOR hole in it, as the smell coming off of the teen as she was rapidly loading her diapers was making her nose burn and her eyes water. 
"R-Rose I think I'm gonna barf if I stay in here, can I go?" She asked, holding her nose for all the good it did. 
"Heh, Yeah, I suppose so. go get the supplies ready for me to change Marinette." Rose said and ruffled Manon's hair, then added. "and er.. Open a window or two..maybe all the windows." 
Manon nodded and took off running, glad to escape the fumes but it was only as she was setting up the changing pad and a fresh diaper it hit her...the diaper change was gonna have to happen in her playroom since thats where everything was!
"Aw man! it's gonna smell like a diaper pail in here for a week!"

Rose oddly found herself ok with the smell. it wasn't that she found it pleasant or anything (Far from it) but some sort of filter of sorts kicked in, Marinette was just a baby and babies sometime stink. 
coming over and rubbing the back of the big baby as she finished up Rose leaned down and kissed Marinette's forehead, which was a little damp from the sheer effort the girl was putting into it.
"Good job Marinette! your SUCH a good diaper pooper! your TOTALLY the stinkiest diaper girl in Paris!" Rose praised, thinking it was a title that the girl wanted. 
Marinette's eyes were a little dull and she gave a silly grin, some drool going down her chin as she finished and then she nodded slowly.
"hehehe Yeah yeah! I make da biggest stinkies!" She coo'ed proudly.
"Heh, you sure do!" Rose gushed and helped the big baby up, breaking out in a laugh as the first attempt saw the training potty stick to Marinette's diaper! "heh, Here, let me help you with that." 
tugging and pulling at the potty, being careful not to rip the diaper open and spill the 'treasure' all over, slowly rose got Marinette freed and couldn't help but giggle as she did so.
'a diaper filling up that much..that's something you only see in cartoons!' she thought but kept it to herself.
With Marinette freed, the big baby swayed on her feet then turned and held out her arms. 
"Uppies?" she asked in the CUTEST voice ever, and Rose almost melted into a puddle.
"Of course!" the blond squealed and with some effort was cradling the big smelly baby in her arms. 
Marinette coo'ed and snuggled into Rose, and then gave her a smooch on the cheek before resting her head. 
"Fankies momma." The pooped stupid Brunette said before drifting off into a well earned nap.
"..ok yeah. I'm calling dibs. she's mine now." Rose said to nobody but herself as she slowly carried her new baby girl towards the playroom for the first of MANY diaper changes. 

The end