"I'm turning you into an anthro Gecko!" She grinned. "It'll be adorable!"
Jake glanced down at the scales already forming on the back of his hand, bright yellow in color, with dozens of dark spots, the pattern continuing as more and more scales began to sprout up his arm toward the rest of his body. He saw his fingers growing just a bit wider, then felt an even weirder sensation on them, starting on the tips and trailing down their length toward the palm. Turning his hands over, Jake each of his fingers were covered in lines of white hair-like structures. Hesitantly, he touched his right pointer finger against the scaled back of his left arm, and found it stuck there.
He shook himself, trying to undo his own sticky grip. Natalie covered her mouth, which didn't do much to hide her hissing laughter as she watched. Finally, with a motion like peeling off tape, he managed to free his hand, letting him see stubby little claws poke through the ends of his fingers, while pale white scales grew over his palm.
He gave a relieved sigh, and then twitched, feeling scales rubbing against his shirt as they grew below it, gradually spreading over the whole of his torso. He twitched again, blinked, felt as if he'd suddenly fell, and when his eyes opened, everything suddenly looked a little bigger, and his clothes felt a little loose. Another twitch, blink, and sinking sensation, and Natalie was practically towering over him, and Jake felt his pants rushing down his increasingly scaly legs and hitting the ground, no longer supported by his waist.
With a yelp much higher pitch than he remembered his voice sounding a few minutes ago, Jake's hands rushed to cover his crotch, though he quickly found that his now-oversized shirt draped down to about his knees, providing some coverage. Were he to guess, he was probably barely even three feet tall.
"Hey!" Jake squeaked up at Natalie, trying to ignore the weird feeling in his feet as his toes went through similar changes to his hands. "What gives? Why're you making me so small?"
"A couple of reasssons." Natalie smirked. "First is you'll look much cuter like this once you're done. Second is as a counter-prank for that time you "helped" me make spaghetti for mom, and I had to spend hours cleaning noodles and tomatoes off the floor. And walls... And the ceiling..."
"For the last time!" Jake crossed his arms and huffed, his growing, spotted tail sticking straight up as he pouted. "That was an accident, not a prank! You know how it is with spaghetti!"
Natalie put a finger to his lips to shush him, even as his jaws and nose began to stretched forward into a snout. "And the last reason was so you'd be light enough to actually try climbing with those new sticky fingers of yours! Might as well have some fun while you're changed, right?"
"You know that if Mom and Dad spot giant marks on the walls and ceiling, I'll be the one to clean them up, right?" Jake pointed out, as his ears shrank back into little holes, his hair vanished, and his eyes grew wider.
Natalie's face fell. "Oh shoot. I knew I was forgetting something."