Declan gulped looking his already swollen body over. At least this would be temporary and he'd be back to his old self in 24 hours. He resigned himself to his fate, there really wasn't any way around it with all of Santa's unexpected tricks. He opened his mouth letting Father Christmas feed him remaining cookie. Like before the growth was nearly immediate.
His moobs swelled larger becoming even more pillow like wrapping around his sides. His gut began to push forward pulling into is lap, What little remained of his neck was now completely lost to the fat roll that was his second chin, framing his round face. His arms and legs grew thicker and meatier. As his butt filled with new layers of fat he could feel himself rise a bit.
Declan's whole body looked soft and round, with his torso resembling a bean bag both in shape and feel.
Declan sat there now nearly 500 lbs, way bigger than anyone he's ever met. The only people he'd ever seen this big were on TV. He couldn't help but trace over his expansive gut, feeling how soft and wobbly it's gotten.
"Ho Ho Ho! Look at you! Now you really are rounder than a bauble" Santa beamed at Declan "Though jelly belly is keeping you modest, your PJs have seen better days. I'll have to fix that!" Santa snapped his finger and the tattered remains of your Pyjamas started to string themselves back together, turning red in the process. Before Declan had a proper chance to react, he was clothed in a form fitting red Onesie, with white collar, cuffs and button strip.
"Thanks... Santa..." Declan said, hoping everything was done now. Things had definitely not gone as plan. He'd just have to wait out these 24 hours, pretend to be sick and not leave his room. He could use that time to work on next years plan.
"Oh quite alright, can't have you go without a wardrobe. After all this year's gift isn't a lump of coal, but you getting to keep your new body permanently." Santa chuckled. "You won't have to worry about losing a pound, not until you learn to be jollier and truly find your Christmas spirit at least." He knew he said he couldn't help Decker, with his wish for Declan to be a good boy, but a little nudging couldn't hurt the young man.
Declan's face went pale white. He couldn't be serious. There was no way he'd really be stuck as this 480 lbs man from now on. "You can't do this!" Declan protested. "I won't try anything like this again! I promise!" he plead.