As he slept, Jon's body shrank all over, as his hair grew out into a curly black mass reminiscent of seaweed. His face was reformed into a vision of young feminine beauty, as large, round breasts grew on his chest. Below, more alarming changes occurred; his waist, just below his belly button, was turning black and smooth and his legs split into many tentacles. As they grew longer, they tapered to a length thinner than his new feminine fingers and formed pinkish pads on the ends. The mass of a dozen or more tentacles was, in a way, reminiscent of a mermaid, retaining its basic feminine shape at the hips and rapidly thinning as it was split into his new lower appendages.
Jon woke up to a scream, and the first thing he saw as his eyes snapped open was the tips of his breasts; beyond that was the reason for the scream, and the reason he screamed as well. "What the fuck?!" he squealed in a higher voice than he went to sleep with, and sat up on his elbows. Pulling a tentacle to him, he let it wrap around his hand, staring in awe.
"Jon? Honey?" his mother said softly, snapping him out of his reverie. "Let's get you to the pool..."
He was in no condition to argue as his mother instructed him to wrap his arms around her, though he did note that she took care to avoid his lower half as she carried his apparently much lighter body through the house. Jon clung to his mother as if she were a life raft, moving his limber tentacles out of harm's way.
"Ready?" she asked as she moved to throw him into the backyard swimming pool. He nodded once and spread his arms out instinctively as she let go, diving and lifting his tentacles up so they wouldn't slap against the pool's edge. In the water he felt completely different. Alive, he might say, feeling every inch of his new anatomy intimately. He let an experimental jet of air out of his siphon, feeling it propel him forward, and flapped his tentacles every which way, though he quickly found out that that didn't get him very far. As he dove underwater he realized that he was no longer breathing, not normally. His gills hidden in the mass of tentacles did so for him.
"Mom?" he called out as he surfaced again, as much to test his new, melodic voice as to assure himself of her presence. "I'm a freak, aren't I?"
His mother was staring sadly at him as he turned to face her, and shook her head. "No, honey, you're not a freak. You've just been transformed. It h-happens to a lot of people," she said, smiling. "I don't think you're a freak."
Jon couldn't find it in himself to smile back. He was, or at least an invalid, confined to water, and half-squid, and a woman to boot. As he dove back underwater, he felt tears welling up, and screamed at the pool's floor, where as loud as he knew he was, he wasn't sure his mom would hear him.