Katie seemed to have a realization about the same time you did as she stares as your blank mer pool toy eyes. She thinks for a moment and slides off you into the pool, leaving you floating erect. She moves her head down to your inflated member, mutters something in a strange language, and then engulfs your penis with her mouth. The feeling of frustration returns as you're receiving a blowjob from an attractive mermaid, but can't do anything about it!
Or can you? A warm sensation soon begins to spread from your crotch across your body. Your body begins to tingle and the feeling of the water against your body begins to change. You begin to lose your feeling of rigidness (well, except for one part of you) as your body changes from a pool toy back to flesh and blood, except you still have a tail.
Finally the change reaches your mouth and you exhale loudly and gasp for air. You sink briefly into the water and Katie's lips and tongue slide off your member. You're briefly disoriented by the change, but you shake the fog clear from your mind.
"Katie?" you ask, wondering where this mysterious neighbor girl/mermaid has gone.
Her head breaks the surface in front of you.
"I'm sorry!" is the first thing she says.
You respond with the obvious: "What the hell happened to me?!"
"You found me and my mermaid friends last night and took a photo of us. We couldn't let you get away with it so I blew you a magical kiss. It was supposed to change you into a mermaid, but I haven't been a mermaid for very long so I guess I botched the incantation."
"You didn't mean to turn me into a pool toy?"
"No! I came over to see if you learned your lesson about spying on mermaids, but decided to go for a swim first and let you wait a little longer. And when I saw the mermaid float I got a little turned on. When the pool toy grew a penis I realized what happened and changed you back."
"With a blowjob?"
"I could have done it with a kiss, but I wanted to do something more apologetic."
"Do you always apologize to guys like that?"
"I've been wanting to do that to you for awhile, but you didn't seem to notice me."
"Oh I noticed you alright. I just figured you weren't interested."
"And now that you know that I am?"