Once the seashore was in view, you both made a beeline for it; running toward the water as if a pair of lost girls catching sight of their dear mother after hours of being separated.
You gasped as your feet hit the chilly waters and let out an audible moan as a wave rolled over your legs. They buckled, and you fell into the water, quickly sliding off your bikini bottom so it would not get in the way of your imminent change. By now, numerous full strands of your hair were illuminated, and your "makeup" and irises were starting to shimmer as well.
Your legs clapped together as you felt the skin and muscles meld together. At the same time, your leg bones disintegrated and began to coalesce onto your tailbone, lengthening it and filling in your tail. It was now starting to turn green as scales began forming on it; but now they reflected the ambient light much better than your temporary tail ever could, even before they luminesced. A broad fluke quickly flared out at the end, accompanied by an almost orgasmic moan from you as your transformation concluded.
"Millie..." Corey, who was still human, gasped, "...you're beautiful!"