Joey wanted to be like Amanda and Samantha so much that he said "I wish that I am a Mermaid like Amanda and Samantha".
He slipped into the water and immediately felt the changes begin. It started with his legs as they merged to become his fins and tails. When it hit his genitals he could feel his cock and balls pull inward to become mermaid female genitalia. It continued upward narrowing his waist. It hit his chest next. His nipples expanded and then his breasts grew outward until he had a D-cup pair of breasts.
The changes continued on as his face became more feminine. His hair grew long and blonde. He looked at his reflection in the water and he was now one of them, a beautiful mermaid. How long was he going to remain like this?