"It's helped my situation because I'll only change you back if you agree to take me to the sea. Like I said, just be thankful I didn't change you into a mermaid," she said.
You ask, “Why would I be thankful?”
"Because ... What!?"
You ignore her shock and say flatly, "I said, why would I be thankful you didn't turn me into a mermaid?"
The mermaid looks at you for a moment and says, "You wanted me to turn you into a mermaid."
"I thought that's what you meant by "be creative", yes."
"That wasn't a question. I told you we're telepathic."
She had certainly said that, but it didn't ring true. "You thought I'd rather be a merman than a mermaid."
She rolled her eyes, "And you thought my tail was a costume."
"It was! I don't get what happened, but after seeing me pick out a mermaid costume even a non-telepathic person should have known I'd rather be a mermaid. How can you be telepathic if you didn't."
"Look, I'm drying out, you're drying out, can we just forget about the finer details of telepathy until we're in the water?"
You didn't like the unanswered questions, but you could feel your tail drying out. "All right, turn me back and I'll get you to the ocean, but then-"
"I know, I have to turn you into a mermaid."
You shook your head, "Not just that, I don't know anything about being a mermaid. If you just turn me into a mermaid and abandon me that would suck, maybe even be a death sentence. You have to show me the ropes. You have to let me tag along until I get the hang of being a mermaid. Deal?"
The mermaid nodded. Your tail felt stiff, then there was the indescribable feeling of your tail splitting in two, soon you had legs. Unfortunately your pants were in tatters on the floor. You assessed the situation and concluded it was largely hopeless. "I can't get you there if I'm naked." Suddenly you felt a strange sensation around your waist, as if someone were trying a silk belt around you. You looked down and saw a ring of white fabric form a loop around you, then it slowly expanded downward until it became a full length skirt. As soon as that was done you felt your penis slowly recede, then invert, and your testicles did the same. There were no words for the feeling as new sexual organs formed withing you. You felt fabric moving around you again, as your panties formed, and then experienced a tingling in your chest.
You cupped a breast in each hand as they formed, they grew until they were the same size as the mermaid's. Again you felt fabric moving across your body, this time on your chest, back, and shoulders as your bra came into being. You looked to the mermaid. She just smiled and said, "You wanted to be female, right?"
After a moment you found your voice, it was delightfully feminine. You hadn't even noticed your larynx change. "We need to cover up your tail," a skirt formed around her tail, much more quickly than yours had formed. "And a wheelchair?" you asked more than stated. As the wheelchair formed itself from nothing you looked in the mirror. Clearly there had been more changes than the ones you noticed. You now looked like an attractive young woman, no trace of maleness was evident. That made you smile.
When you put her in the wheelchair the mermaid looked like any other woman in a wheelchair, she even grew a shirt to cover her seashell bikini. You rolled the her out of the store, out of the mall, and towards the nearest beach. With every step you took you noticed the unfamiliar motion of your breasts, and loved every moment of it. For the first time in your life it seemed like everything was going right.
The beach wasn't far. When you got there you found that the wheelchair wouldn't roll through the sand so you carried her into the water. Once you were deep enough for her to swim she said, "Now its time for my end, are you ready?"
for a moment you had doubt. Would she keep to the deal, or might she turn you into a fish. Even if she did turn you into a mermaid, would she look after you, or abandon you. You pushed the doubt aside and said, "Yes." Your panties were destroyed much as your pants had been before. When your tail finished forming you wriggled out of your skirt, and tested it in the water. It was strong and you were sure you could move quite fast, much faster than any human.
You found that there was no end of things to be happy about, you were a mermaid, you could live in the water for the rest of your life and never have to put up with human stupidity again. You loved your breasts. You pulled off the silly human shirt that was covering them, and let it float away. You looked at the bra you were wearing and thought that you'd much rather have a shell bikini like the mermaid. Then suddenly it changed, the front hardened, the straps changed to twine, and when it finished it was a shell bikini.
"Like it?" the mermaid asked.
"How did you-"
"I told you, we're telepathic. Come on." And she swam away from shore. At the beginning of the day you were thinking about your girlfriend's dress party, such a silly human concern. Now you were swimming free as a mermaid. Maybe you'd go back and see if your girlfriend wanted to join you as a mermaid, but you never wanted to go back to being human. You followed the other mermaid as she led you into the open ocean.