Ben looked back at the garage door as it closed and therefore did not notice you tip toeing next to him. When he looked back around you literally jump into his arms as he catches you reflexively. Planting a passionate kiss on his mouth you can feel any and all resistance melt away. He gently places you on the cold concrete as he strips of his pants and you your skirt.
Ben takes no time to thrust his engorged penis into your sopping wet vagina. His strokes start out slow but pick up in speed as you two get going.
"OOOO" you scream, clenching your vaginal muscles as tightly as you can as Ben comes deep inside you. Both of you collapse onto the floor relaxing in orgasmic bliss. Recovering first you wonder if he is ready to go again as you sit up. Looking over at your sleeping partner you can't help but notice that something is off. His once tight pecs seems a little softer, his nipples larger and erect. Suddenly you realize that you have spread your condition to Ben.
Deciding to leave before he was beyond recovery you try to stand up only to find that your legs had begun to fuse together. Starting at your waste the skin between your thighs had fused together and was slowly spreading downward. This skin turning a dolphin grey as it did so.
Turning toward Ben you shake him awake. "You have to take me to the beach."
Ben still slightly groggy looks at you "Take you where?"
"To the beach you big dummy! I need to get back into the ocean."
Ben sits up oblivious to his own changes for now as he watch you slowly turn into a mermaid. "Okay, I guess."
He gathers his clothes and picks you up and at your direction places you into the passengers seat of the truck. Starting up the van and opening the garage door Ben starts driving you to the beach. Still unaware of his second passenger.