Nate continues to laugh at your predicament, squealing like...well, a pig. Strangely, though, he hasn't changed any physically.
"Get a grip, man," you say. "We've got to start moving some balloons if we don't want this to get any worse."
Nate has been rolling on the ground laughing, but it seems he's regained a little control. He struggles to stand up, but when he does it becomes apparent what's changed about him.
"Dude, you're huge!"
Nate looks at you, dumbfounded. "What OINK do yo-oink-ou me-EEE-n?" With each grunt and squeal, he grows a little more fat. Were the bulk made of fat, you think he'd weight at least 275, maybe even 300! As it is, he weighs considerably less as he's just filled with air. "Oh my-SNORT God!" he screams, his waste growing another inch.
Stranger still, his still-human skin--even on his arms and face--has taken on a pinkish tone.
"What OINK has that SNORT fuuuUUUuucker done to me-EEEEEE!?!" Nate yells, growing larger and flushing pinker.
"Well, Pig-Nate," the balloon seller says from behind you, "I suppose this will motivate you a little more."
You both turn to see the balloon seller has reappeared. "Now," the seller says, "you'd better get to selling those balloons."