Story #9: Just a Costume

(This is a picture that was voted on by my Patrons! It comes from a story that is exclusive to my premium $10 tier on Patreon. I may create that tier on here as well, so I can post the rest of those stories!) Story #9: Just a Costume: He hadn't thought much about the costume that she had picked out for him. When his girlfriend had mentioned that she wanted to go to a Halloween party, he hadn't been particularly jazzed, but he'd begrudgingly agreed; he didn't know many of the people that would be there, and Halloween seemed rather... Juvenile. She had sweet-talked him though and ultimately he had relented, under the condition that they'd only be there for a few hours, and that she'd take care of all the coordination. She had seemed all too happy to manage the arrangements and told him that he only needed to keep his calendar and mind open. When the night had come, she had presented him with what their costumes would be: a naughty nanny and her more traditionally naughty charge. She of course looked amazing, which is why he had probably been so willing to overlook how much less attractive his own costume was. It didn't seem odd to him though; after all, the 'big baby' was hardly the most thrilling or dignified costume, but it wasn't exactly an uncommon idea. At worst, he might get cold or take the brunt of some drunken jokes. As she helped him get situated into the giant costume diaper and the other paraphernalia, such as an oversized bib and bonnet, he couldn't help but notice how much more relaxed she had been the last few weeks. Their relationship had been troubled. She worked hard and long to keep the lights on, and he was 'still looking', a solid six months after getting fired from his last job. He wasn't exactly accommodating as a homemaker either, instead just slovenly sprawling across the couch and binging Netflix. Things had almost reached a breaking point, but ever since he agreed to go to this party, she had seemingly done a full switch and had been completely unperturbed by the lazy slob that she came home to. He should have allowed himself to be more curious, to be more intellectually engaged, but he'd just accepted it. It was the path of least resistance and that was good enough for him. It would only be the future clarity of what these signs meant that granted him the incredible ability of hindsight. She drove them to the party, which was another prior contention, since he'd defaulted on his car note and had his own repossessed. She made a few playful jeers about him needing a car-seat, but he took it in good fun. Spirits were high. The party was about what he expected. It was mostly friends of his girlfriend, and other assorted strangers. He knew a few guys there, though only because they were dating the aforementioned friends. As he anticipated, his costume aroused an unwelcome attention from the other adults, who couldn't help but make all the obvious jokes and pat his puffy rump. It took a few beers to get comfortable, and then a few more to really get comfortable; less than an hour in and he was already shitfaced, or at least rapidly approaching it. The aching in his bladder didn't take long to follow and he awkwardly began to waddle around in search of the bathroom. It was so noisy and congested that he couldn't even think straight, and shamefully, he stopped to ask one of the girls that he recognized. She laughed in his face and squeezed the front of the costume diaper, "Don't be silly! Your potty is right here, little guy!" His face was already red with inebriation, so his embarrassment didn't show, but even in his drunken state, he knew that he was being rudely mocked. "Issh jussta' costoom! Yooou...stooopid bish.." He slurred, suddenly feeling that this was maybe a little more than just the effects of his careless drinking. "You sure about that? I think I feel tinkles!" The woman said in a sing song voice, still gripping firmly at his padded crotch. He was going to tell her off again, but he could suddenly feel it. A pooling warmth around his groin, and the intense euphoria of release. "I...no...I no pee-pee.." He managed to sputter out, though it lacked any confidence of an adult man and instead mirrored the unsure mewling of a hapless toddler. "I think you did, mister. You had to piddle lots! Good thing your mommy put you in such a big diaper." Her hand moved from his swollen diaper and the yellow stain was unmistakable. He just stared at it in a dull horror, his brain teetering on the brink of full-blown panic. As if to punctuate the moment, he suddenly let loose and ripped a giant fart into his diaper. It was almost surely karmic justice for the dinner that he'd greedily hogged the lion's share of, while his girlfriend had just smiled and said nothing. "Need da' potty! Gotta make...Mmph.. Gonna make poopies!" He grunted, suddenly clenching his buttcheeks helplessly, even as another toot squeaked out against his defenses. "Poopies huh? Are they going to be big poopies?" The woman asked with a smile that was getting more cruel. "Won't that be a first? You actually doing some business and bringing something to show your girlfriend.." His expression was slack-jawed, and at this point, his chin was becoming slick with drool. The cramps in his belly were becoming more unruly and despite his best efforts, he was still peppering his giant diaper with plenty of noisy gasbombs. It felt as if even the process of using the toilet was starting to fade from his mind, like it was again becoming an enigma. His mind was so focused on the urgent need to poop, that it didn't even register that the woman had shown her hand. He suddenly felt a swift swat against his thickly padded ass, which only seemed to result in more errant gas as a response. "There you are! I turn around for one minute and you toddle off somewhere. Maybe I should have brought a leash too." It was his girlfriend, and while it sounded kinky on a surface level, there was a frightening feeling that her tone was genuine. He tilted his head back, his bonnet swaying with the movement: "Me gotta potty! Me gotta make ca-ca!" The man loudly announced. "I bet. You were a little piggy at dinner time, and now...Well, I guess what goes in, must come out...Well, don't worry about it, sweetie. I know the package said that the diaper is just a part of the costume, but I think it'll do just fine for the evening." She teased, before putting her hands on his shoulders and starting to gently lead him downward into a squatting position. The effect was instantaneous. The giant costume diaper was suddenly turned into the crash zone of an out-of-control log flume ride. More people ended up stopping by to watch, as the noisy evacuation had been impossible to ignore. He was pinching loaf after loaf in his diaper, seat getting lumpier by the moment, all while he soaked the novelty bib in a stupid straining drool. His girlfriend squeezed the lumpy backside of the diaper and laughed, "Wow, baby...You really got some mileage here...You know its just supposed to be a costume, right?" She teased. He grunted and felt another big load squeeze out, the warm fabric expanding against her palm. She clicked her tongue and continued: "...That's okay, I knew that you'd fit right where you needed to. Halloween should be about dressing like something you're not, but let's be honest, this is what you are without all the pomp and circumstance. Just a dumb, lazy, oversized baby that needs 'mommy' to do everything for you." He was too preoccupied with his ongoing bowel movement to give her monologue the undivided attention it deserved. "I need a real man in my life. Someone who can provide for me in ways that you've proven inept. I thought about just dumping you, but...Well, I know you'd never make it on your own. Nothing will really change for you, except your diapers; well...When I'm not busy, of course." She callously explained, still groping at his still-expanding seat, with a malicious aggression that was meant to degrade him. "You'll learn to love it. Well, if you're capable of learning anything anymore...The stuff I put in your food at dinner was pretty experimental, so I honestly don't know just how much of your brain it's going to melt." There was a final gassy crescendo, culminating in the sounds of rapid, hefty plopping. The man's mind was now mush, no more intellectually viable than the mush he had just devastated his diaper with. The costume hadn't been the diaper, bonnet, and bib. The costume had been pretending to be a functional, respectable adult for so long. But that had just been a costume, and now this was the real thing.