Millie's lungs were bursting - she knew that if she stayed down any longer, she'd drown - Flip would be okay though, dolphins could hold their breaths for up to 8-10 minutes.
Millie started going lightheaded as her brain pounded, her vision blurring even further as she flailed her leg-arms about to try and propel her body. Her body made the involuntary gasp for air - and suddenly Millie could breathe.
She felt her skin shift on the sides of her neck and just above her hips, as three, horizontal slits opened up in all four positions.
Millie, now effectively breathing water, awkwardly bent her legs backward and whirled them around, touching the slits on the side of her neck and examining the ones on her sides.
Mammalian gills?
Millie was also surprised at how flexible her now shoulder-mounted legs were - and how well she could see - it felt like as if her eyeballs had a swimming goggle-like, transparent, extra "eyelid" right on top of them.
A bizarre sensation occurred in Millie's feet as they began to split painlessly between their middle and fourth toes, bending outwards as if in a split fan-like shape.
Millie was even more confused about what was going on until she felt an odd "popping" sensation on her feet.
Suddenly, tiny, silver-bluish-brownish scales appeared, spreading up from Millie's feet to her thighs and soon up to her shoulders, spilling a bit onto the sides of her chest, back, stomach, buttocks, and neck before stopping, transforming her backwards-facing legs into large, backwards-facing shoulder-mounted mermaid tails, her feet now splayed into wonderful but bony fish tails.
Millie recognized the scales and their feel, and the tails she now had - they were mackerel, the fish she had given Flip that day.
Millie was about to turn to see what had happened to Flip, bummed that she was now a weird-looking armless, "legless" mermaid, when she felt more bizarre sensations going on -
With a pop - she felt a large bony object grow on her back that she could control - turning, she recognized it to be the dorsal fin of a mackerel.
Millie felt an odd, pleasurable sensation between her breasts, still covered by her now sleeveless shirt, and, arching her back, had to gasp and moan quietly as a third breast popped into existence between her existing two.
The most incredulous of Millie's changes occurred when she felt a pressure in her groin - on her vagina, to be exact.
Her still (but loosely) attached cargo pants and underwear to her legless hips were pushed away as, quite pleasurably, Millie felt her vagina protrude into a funnel shape.
Millie wondered what the growing bulge was. A penis?
Quite the contrary.
It was a human female arm, covered slightly in mackerel scales, that ended into two hands attached to the wrist, one right, and one left, splayed outwards to form a fish-tail like shape.