You begin to get horny. You feel your penis stiffen in your swim shorts as you swim close to her, pressing it against her long red tail. She grins seductivly and kisses you. Your face turns red and you kiss back grinning. She slowly pushes you down below the water on the sand, however you could breath as she kissed you. She slowly moved her nimble arms towards yours and slowly held your hands. Then, she forced them onto the sand. Making you unable to move them. She grabbed some nearby seaweed tying them each to a rock so you couldn't raise them. She did the same to your legs. She gently removed your shorts exposing your cock as a hole emerged near her crotch. You quickly calmed down as she came closer. She slowly laid on you as you grinned. It felt so nice inside. But, something felt odd. You watched as your arms and legs began becoming smooth and hairless as they became nimble and small. You watched as your brown hair grew longer and longer nearly reaching your waist. You felt your stomach suck in and your waist widen as your rear bulged more. You began to feel very strange and asked aloud." W-What are you doing to me!?" Although your voice slowly became softer and attractive as you said it. Your penis felt strange. Like you couldn't move it. You looked down and saw yours flatten against your body, and reemerge the opposite way from the mermaid!" What's happening to me?!" You yelled freightened and weak. She grinned widely as her hair grew shorter and shorter until it was like a mans. Her chest grew large and strong. She grew light stuble and her face grew large. Her chest flattened as she removed her red clam shell bra. Her tail were no longer one appendage but two legs, that soon grew hair and became manly like her arms. You had no idea what would happen next! She slowly untied your hands, and you tried to fight it, but she pressed your arms back down hard as (H)she pressed his cock against your smooth skin. She gently pulled the clan bra up grabbing it and wrapping the wrap holding it together around you. Your nipples felt hard and erect. They pushed outward as you soon began to have breasts. They grew to a fairly nice size. You gasped as you realized what was happening." Stop!" You said in your new voice. "I will soon enough." She said in a deep voice. Your legs felt tingly. They began to come together as the seaweed snapped. Your knees smashed together as your legs binded, you wriggled for about 30 seconds trying to stop it until they felt as one appendage. Your feet went numb as your toes slowly disappeared and your feet connected and flattened out into a large fin. A light ring formed around your waist like Merfolk in the little mermaid. Red scales quickly formed over your tail as Gil's came too. The only thing that would be able to change you was if you could get his penis back before the hole closed. You tried to stop him from leaving but the changes were nearly complete he tugged your hair forcing you to yell which soon turned to beautiful singing as you covered your mouth and moaned in pain. Your last human cells were being killed off as your transformation completed.