"You really want a mermaid, don't you?" Jon asked. The lead hunter snorted. "Damn straight! Do you know how much we could fetch for that thing?"
"Quite a bit, I suppose," Jon mused. "And you two? I guess you want a mermaid just as badly, huh?" The other two men nodded. Jon sighed. "All right, I'll tell you what. Cut me in on the deal, and I'll get you three mermaids. Okay?"
The leader eyed him suspiciously. "For how much?"
"We'll split it four ways," Jon said. "I give you three mermaids, you give me twenty-five percent of whatever you get for them. Deal?"
The lead hunter glanced at his two companions, who nodded their assent. "Deal," he said. "Bring 'em out."
Jon nodded and gripped the rock. "I wish you didn't have guns with you," he said. "They're so much harder to trick when you're carrying a weapon. But let's see what I can do."
The hunters were watching the lake so intensely that they failed to notice that Jon's wish had made their guns disappear. Jon smiled devilishly. "All right," he said. "You three want mermaids so badly? I wish you were mermaids yourselves."
The three hunters stared at him in annoyed disbelief, wondering if this was some kind of joke, until they began to feel strange. Looking down, the leader saw that his pants had disappeared and his legs were fusing together. His scream caught the attention of the other two, who noticed that the same thing was happening to them. While they began to panic, Jon hoofed it a few hundred feet down the shore, just in case.
In the meantime, all three had had their legs finish fusing, with the bone structures replaced by an extended spine. By this point, their proto-tails were much more flexible than rigid, and completely unable to support the weight of their bodies in a standing position. All three of them slumped to the ground, which was just as well now that their feet had begun to reshape into tailfins. The three ex-hunters were screaming their lungs out as scales began to cover their lower bodies; the leader had emerald green, one of his companions had iridescent blue, and the other had salmon pink.
Jon was getting tired of all the screaming, but once the three men's hair began to grow out, the screams changed to muted whimpering. In the process, their hair became soft and silky, changing color to match their scales, with the green-scaled one becoming blonde, the blue-scaled one's hair becoming a lighter brown than it already was, and the pink-scaled one's hair becoming jet black.
As this happened, the clothes vanished off of their upper bodies as well, just in time for them to watch their human halves change shape. All three changed from their stocky, angular masculine builds to curvy, feminine bodies, their faces becoming soft and finer, their nipples blossoming into breasts that completed their full, shapely figures. As they watched, their male genitals were retracted into their tails, hidden behind barely-visible slits in the skin; but before long, the slits were all that was left, and they were completely female.
Jon walked up to the ex-hunters. They stared at him, wide-eyed and frightened. Trembling, the leader opened her mouth. "Wh-what did you d-do to us?" she asked, her voice now soft and high. Jon smirked. "I delivered on my promise," he said. "You have three mermaids, so you owe me a quarter of whatever you get for them. Of course, if you don't feel like selling yourselves, I would suggest that you get underwater pretty quick. The lake is an okay place to hide, but I hear that every now and then some asshole will come along and try to kidnap its occupants."
With that, Jon turned and walked away, leaving the three new mermaids to face their new lives.
