Suddenly, you feel your legs starting to tickle. You look down to see scales growing on your legs. You reach down to feel them and you find out that your hands are growing smaller and your fingers are growing longer. You feel a tickling in your scalp it starts to go down to your shoulders. You reach back and find out that your hair is growing longer. It keeps growing until it reaches your waist. You feel your face shifting around and you shrink a little. Your chest starts tickling, and you look down and see your nipples growing bigger. Two A cup breasts stick out of your chest. A bra made of shells appears over your new pert breasts. You can feel them on your now sensitive titties. Your legs continue morphing into a tail, and you look at your reflection in the water. You are now a thirteen-year-old mermaid.