"Oh no, I'm getting smaller!" Archie said, seeing himself shrink.
Archie was now much less than half his proper height, less than a quarter even. He managed to crawl out of his clothes before reaching up helplessly toward the garden furniture he'd been sitting in, which now towered above him. He hoped he wasn't about to simply shrink away to nothing.
It was when he was naked when he noticed bumps on his sides that he could wiggle back and forth. They seemed to be getting longer as he watched.
"Am I turning into a bug?" he wondered. As if to answer his question, a pair of thin protrusions pressed out from his head. They stretched longer and longer and started twitching to sample different positions in the air. He could smell the grass and dirt and what he would soon discover to be pheromones from the other insects around him.
He couldn't help but wonder what was happening to all of his body mass as he noticed that even his shoes were now larger than him. His arms and legs had stretched and thinned and no looked almost identical to the appendages that had grown out of his middle. He was resting on all six of them, and they all had a surprisingly good grip on the ground beneath him from what he could tell. At last he was a 4 centimetres-long insect with a black body and relatively long legs, with clear wings. He was able to start flying with his wings over toward the nearby tree, and he knew it looked way more awkward than it felt. He soon realized what he had become.
He had become a fly, but his human head was still on his fly body.
"Holy cow." Archie muttered. "This is.... more than I was expecting."