When next I awoke, I was partially submerged in water, still in the grotto somewhere. The lights had deepened back to blue, but I suddenly realized that I could see perfectly clearly!
Where before I had seen shadows, I saw young women with hair like seaweed, skin tones ranging from fair to ocean-green, and tails of varying hues. They clustered around me, very curious, but keeping a distance, not coming within a few feet of me.
"Hello," I said, and cut myself off. My voice sounded extremely odd. Almost a croak, or a sort of gargling sound.
That was when I looked down and saw my body. From my waist down I had a long blue tail that made my total body length about 10 feet!
What had they done to me?
"You are awake," came a voice. "Good."
It sounded a little bit familiar. I turned to see a tall woman, probably about my height - well, what my height was before they turned me into a fish. She was naked, and I turned my eyes away, abashed. Who was she? Had she been captured like me? Why hadn't they turned her into--?
Then it hit me. That was the merwoman who had captured me! How was she a human now? And I a... Jesu. She had somehow switched with me. From merwoman and man to woman and merman.
"Why?" I croaked in my strange new voice.
"My daughters," she said imperiously, "are the daughters of Neptune, Old Man of the Sea. He has slept many hundreds of years, and when he will wake, none know. But his children are his greatest treasures, and I would keep them safe. I go to man's world seeking a guardian. A wizard, perhaps."
I snorted, the sound a bit strange since I had gills as well as lungs. "There are no such thing as wizards."
She laughed. "Nor, I suppose, any such thing as merpeople?"
She had me there. "Well, why keep me around? Let me go! And, uh, turn me back?"
"You shall be my guardian while I am gone. Hopefully that will be enough to deter any plunderers until a REAL guardian can be appointed."
Despite everything, I bristled that I didn't seem capable enough for the job to her. Chalk it up to masculine pride. "Well, why should I help you?" I demanded. "You captured me, and changed me into... this."
She chuckled. "Try and leave my daughters alone. You will find you can't. I have placed a geas on you, such that, as soon as I am gone, you will desire nothing more than to protect and guard them."
Panic started clawing its way up from my gut. She had... controlled my mind somehow?
She pointed to the purple crystal. "If you need help, touch this crystal, and help shall come. But use it only in the direst need, for it invokes an ancient pact that once invoked, expires."
"Alright," I managed, "and when you return, you'll... turn me back?"
"And let me go?"
Her voice was cold. "No. I shall kill you."
And then she was gone, and I was left with the mermaids.