Water splashes onto the pool deck from Lydia's impact on the water. A few moments later, your girlfriend pokes her head out of water.
"See how you like it!" Lydia says playfully.
Her head disappears under the water again and a moment later pool water sprays in your direction. You catch a brief glimpse of Lydia's tailfin flinging the water from the pool. Some of it catches you, getting you wet but not totally soaked. If Lydia had her tail for longer than half an hour she might've had the aim to get you completely drenched. You walk out to the pool's edge. No longer under the cover of the roof overhang by the door, the rain is now falling through the screen on you and you're sure to be soaked before long.
You watch as Lydia swims underwater, from one end of the pool to another. You've seen her swim before but seeing her swim as a mermaid is unique and special. She's propelling herself with her tail faster than she could with legs and turning around at each end in a way that wouldn't be possible if she didn't have the flexibility of a tail. She blows a kiss to you from under the water as she does another lap. On another lap, she swims toward the surface at an angle but angles back downard near the surface. The effect of curling her back in that move really accentuates her breasts.
You start to feel a chill from being soaked and remember you'd taken off your shirt in Lydia's room and never put it back on. You also try to hold your legs together to not make your excitement too obvious.
Lydia breaks the surface of the water in front of you, putting her hands on the edge of the pool and pulling herself part way out in front of you. She thrusts her breasts out toward you and gives you a smile. She's teasing you like never before in the time you've known her.
"Liking what you see?"
You look over her beautiful face, her long hair spilling around her shoulders, her perflectly sized breasts, her impossibly smooth spandex skin - all further defined by the water running down her body. You're speachless. Your only response is a nervous swallow.