Greg went into the bathroom, undressed, and turned on the shower. The bottle's contents had drenched his torso and was now running down his legs. It seemed impossible how much liquid had been in such a small bottle. Stepping into the shower felt amazing and he immediately got a hard on. He stroked his penis a few times and found whatever the bottle had been intended for its contents made a great lubricant.
Just then the shower door opened and Joanna stepped in, naked.
"Why take two showers when we can take one together?"
They embraced and kissed under the falling water. Greg received a pleasant jolt when Joanna touched his chest; that part of his body seemed unusually sensitive. Neither remarked on it, but both noticed the air smelled strongly of the ocean.
The two continued to kiss and caress, as Joanna noticed Greg's skin felt usually smooth thanks to whatever was in the bottle. Some kind of moisturizer, she wondered. Touching Greg's penis she found out how slick it was. She rubbed her hands over Greg's body, getting as much of the substance on her hands as possible then stroking him with one hand while rubbing her crotch with the other. Finally Greg pressed Joanna against the wall, sliding into her and causing her eyes to go wide. Whatever the substance was, it made sex seem frictionless while also extra sensitive. The old woman's words that morning about choosing your fate crossed Joanna's mind - was her fate to have great sex? That seemed like a pretty good fate. Moments later, they both orgasmed and collapsed.
As they both sat in the shower, backs against the tile, Greg felt very strange. His chest felt very warm and his crotch felt like someone had dumped cold water on it. Greg rubbed his chest absentmindedly.
Joanna chuckled. "You look like me playing with my breasts."
Greg looked down and realized she was right: he was basically fondling himself. But shockingly he now had mounds of flesh big enough to fondle! "What the hell?!"
"How do you have breasts?" Joanna gasped.
She touched them to make sure they were real and Greg moaned in a way that sounded more feminine than masculine. Joanna noticed part of Greg's body was glistening in the water from the shower and found scattered scales trailing down from his swelling bosoms toward his waist, scales like those of a fish.
Before Joanna could investigate further, Greg suddenly doubled over and groaned. In doing so, Joanna saw his hair that had been short when she arrived home was now down to his shoulders. She suddenly had a terrible idea of what the contents of a bottle called Mermaid Scales really did. She helped Greg to sit back up and saw what she expected: Greg's legs beginning to draw together, as if slowly being zipped downward toward his feet; scales spreading over his legs, and a noticable absence of his manhood.
"Oh, Greg, you're turning into a mermaid!"
Greg didn't respond, seemingly in a daze. Then it occurred to Joanna how much Greg's body had been pressed against and inserted into her. Checking her hands, she found fleshy webbing growing between her fingers and scales on the back of her hands. And spreading outward from her vagina were scales. She was turning into a mermaid too.