When Laios and his friends found out he was unable to feel full, everyone believed, at first, that he still had the same stomach capacity as before; that while not able to feel the pleasure that comes with it, the pressure excerted onto his gut would still allow him to understand his limits, or at the very least vomit if he overexerted himself. Still, worried as they were, they kept a close eye on his alimentation, keeping his diet balanced and the portions limited.
However, after the initial wave of worry had settled down, the constant surveilance on His Majesty's appetite weakened, and one night he managed to sneak out to a cheesecake eating competition accompanied by Kabru, who let him go driven by love and stayed by his side driven by worry (and, of course, a wicked sense of curiosity).
The tavern where the competition held place was more akin to a patisserie than the more bar-ish places where he used to go to with his friends: Cakes, croissants and other sweet pastries were lined up in a glass display alongside sweet liquors and high quality booze; the tables, small and round, were all placed on the ends of the L-shaped building, where patrons and viewers could sit and snack while watching the competition and betting on a winner. The owner, a somewhat shady-looking half-dressed middle-aged fat tallman stood behind the counter, letting his sprawling gut rest on the counter reserved for half-foots while flirtatiously chatting with some of the contestants.
Laios, who had just learned a face-changing spell, went unrecognised within the crowd of chellengers, who were, unsurprisingly, three times his size on average. Of course, skinnier rivals were also present, but almost all of them were kobolds, who by nature have a much higher capacity.
The competition started, and as expected the most favourable contestants were gluttonous enough to forego the usage of regular forks and instead use the cake shovel to stuff themselves. Slice after slice the monoliths finished whole cakes in a manner of minutes, while Laios and the other underlings were barely halfway through their first cake, some struggling already. That's when Kabru, jokingly, told Laios to imitate them, somehow managing to match the speed of the much bigger contestants, finishing cake after cake after cake with them, overwhelmed by the sweetness of such banquet, he slowly stopped thinking, only relishing in the taste of the berry cream and the buttery biscuit crust.
The crowd was shook: how could such a small guy fit that much cheesecake inside of him? Kabru, of course, was very, very interested in this unexpected ability of his, as it proved the theory of a maximum capacity false. So then, where does the cake actually go?
After the tenth cheesecake eaten by his mindless companion, it finally hit him, quite literally in fact, as the button right in the middle of Laios's belly flew off his shredding shirt right onto Kabru's forehead. Buttons popping was definitely not uncommon in theese types of competition: it's something that people bet on and that crowds go wild for, eating so much that clothes can't contain you. His shirt getting a couple of tears wouldn't have been that big a deal, however...
"That shirt wasn't that tight." He thought. "We got it especially for this occasion. It was supposed to be about three sizes too big so that no one could recognize him, even from his body." And yet, without a doubt, that shirt had gotten significately tighter thorughout the competition: the sleeves, torn vertically, showed previously nonexistent stretch marks; his pants, which he had already unbuttoned for comfort, were unsalvageable, split open on both sides from the waist to the knees; his belly, now a proper gut, sat extended onto his widening lap, proudly displaying the deepening navel which had just gotten laid bare; newly formed love handles folded neatly atop his fattening ass which in turn not even his chin was safe, becoming puffier with every bite.
Laios had gained around 50lb (23kg) in just one sitting. The slices he swallowed were instantly churned into body fat, of which he had a rapidly increasing excess of.
All other contestants had either given up or where about to, meanwhile Laios kept on eating. The crowd was... Worried? Angry? Most of them were just enamoured with the way his curves kept excentuating; he didn't even need to ask for more cake as the bartenders just decided to keep feeding him for as long as he had any will to eat.
10 cakes became 15, which in turn became 20, and he still wouldn't stop gorging himself. He had already won, but no one could stop staring. Some asked if they could feed him directly (their requests were politely declined), the other contestants were feeling jealous of such prowace. Kabru was found out as his lover, and everyone who wasn't entranced by his belly naked (all buttons flew off) boyfriend were asking him what was the trick behind such rapid weight gain.
Jealousy. 300lb was the new weight of the king, and Kabru just couldn't stand the situation anymore. Everyone was staring at the man he loves while he himself had to deal with the knowledge that he, too, was enjoying this transformation. Despite the crowd and the tavern's personnel's begging, he called the contest off, asking that Laios be disqualified. Laios himself, unaware of the clamor around him, was only able to snap out of his trance after Kabru had dragged him by the collar out of the tavern while he was eating.
"Huff, that was sooo good Kabru! We should do this tomorrow too!"
Kabru looked at him, dumbfounded yet also deeply aroused: "Oh, so now you can speak?"
"Huh? What does that mean?"
As Laios began caressing his barren, distended belly, he slowly realized the change in his body. He'd gotten fatter. Extremely fatter. in just under two hours, he'd gained half his original body weight.
"What... What is this?" He said, grabbing the unfamiliar love handles sitting on his waist.
"Oh, that?" Kabru scoffed, blushing. "That's just the result of the twenty cheesecakes you just ate."
"Tw-TWENTY???" Yelled Laios. Kabru puts his finger on his lips tu shush him.
Laios continues: "...Is it bad that I'd like some more?"
This is the end of part one of a fic I'd like to continue! I'm plenty unmotivated by nature, but if you enjoyed it let me know, and I'll try to finish part two sooner!