Maybe it was the fact that she seemed to be sleeping on her arms rather than her pillow. Maybe it was the fact that Celestia didn't seem to be sleeping on a pillow or a bed at all, but rather on something hard, cold and wet. Maybe it was the fact that rather than feeling the soft touch of her bedsheets upon on her body, she felt as if everything below her navel was below water. Maybe it was the fact that Celestia felt that there was something different with her legs and her chest. Maybe, just maybe, it was all of these things combined.
But how can that be? She knew beyond any shadow of a doubt that she came to her ordinary house and that night she slept on her ordinary bed.
Faced with these facts, Celestia decided to open her eyes. The sight was not of her bedroom, but rather the beach. She remembered seeing some of it in Sunset Shimmer's yearbook foto, for both Celestia and vice-principal Luna was part of the yearbook committee. They would give final approval before the yearbook is released to the whole school to read.
But that was pushed aside for the moment as Celestia glanced down. The sight was not of her bed and pillow, but rather a small rock that was above the water. Farther down, however, she saw that not only were her breasts bigger, but they were also bare. How did she end up topless, or worse, naked on a public beach overnight?
Celestia sat with her back against the rock, leaving her now large breasts exposed, but that didn't seem to bother her for some reason. Maybe it was because it was early morning, there wasn't anyone on the beach yet. She cupped both her breasts in her hands. What was once cup size C had grown to DD breasts.
But as Celestia sat there examining her breasts, she couldn't shake the feeling that her legs felt strange. She slowly raised what she thought was her legs out of the water.
But it wasn't two human legs that came into view, but rather a moderate cornflower blue fishtail. She had become a mermaid. Celestia let out a delightful gasp. She loved it! Ever since the incident with The Dazzlings, she gained a hidden interest in the mysteries of the deep, specifically regarding whether or not mermaids existed. And here she was as a real mermaid.
While she was feeling her new appendage she got insanely aroused. A thought entered her mind. She ran her hand down her tail until... Bingo! Somewhere in her pelvic area, she had found a cunningly hidden slit. It was certainly more sensitive than the rest of her tail. She figured that these were her outer labia, but they were blue and scaley like the rest of her tail.
As she sat there, Celestia decided...