After staring at the tails growing out of people's backs, you suddenly notice you're standing in the water yourself. Fearing for your body, you quickly take your feet out of the water...too late. Your toes have a lot more distance between them, with slimy webbing filling the gaps. In fact, your entire feet are slimy...and starting to acquire a green-brown tint. You try to run away from the water, but the best you can do is make small hops on these webbed feet. The green slimy skin has started to crawl up your leg by now, also making your legs shorter and thicker until they're almost as long as your arms. Your internal bone structure is softening and slowly feel yourself sliding into a crouched position, until you're practically sitting on your legs, your hands straight in front of you on the wet sand of the beach with the same kind of webbing between your slimy fingers. The brown spotted pattern covers your entire body by now, providing a contrast to the slimy green. You try to speak as you feel your mouth broaden across your face, but all you can produce is a low croak, quickly followed by a ribbit as you discover your new ability to make your chest expand. You make your tongue shoot out of your mouth and are surprised by its incredible length while the changes to your face continue as your nose and ears recede into your skull, your eyes sliding to the side of your head and inflating to emotionless yellow bulbs.
You have lost much of your humanity, but despite your amphibian exterior you seem to have retained a semblance of your former self...you have practically become a human-sized frog, or a frogman if you will.