Beth went to her room and changed into her bikini, reading herself for a swim. My wife and Beth's sister Julie walked into the living room and sat down on the sofa. I gave them a quick glance, wondering if they had any idea what Beth and I had done while they were away. Beth returned to the room wearing what had to be the smallest bikini top I had ever seen. Her full tits strained against the material and for an instant I thought they would pop free. Her nipples were almost visible and I knew once she got wet that they would shine through.
"Does anyone want to go swimming with me?" she asked.
My wife and Julie both declined, my wife said she was too tired and wanted to take a nap and Julie said she had to do some research on some colleges she was thinking about applying to.
"How about you Dad, you never go swimming anymore." Beth said, smiling at me.
My cock sprang back to life and began to swell once again.
"Well it is getting kind of late, but I guess I can join you for a little while." I replied, smiling back at her.
I got up and walked as slowly as I could back to my bedroom to change. My cock was at half-mast and hung down impressively. I was startled when my wife walked into the room and said she was going to take a nap back here. I stood before her naked with my cock hardening and hoped she wouldn't put two and two together. My wife sat on the bed and reached out for my tool.
"Maybe you shouldn't go swimming but stay back here and 'nap' with me." She laughed, squeezing my cock.
"That's ok," I told her, "you go ahead and take your nap, I promise to wake you later and we can play then."
She nodded and lay back on the bed. I finished getting dressed and walked out the door quietly, I could already her the quiet pace of my wife's breathing as she had quickly fallen asleep My cock continued to swell in the freedom of the swim trunks. I grabbed a towel and quickly walked out to the pool.
Beth was already swimming when I walked up and she just smiled at me as I got into the pool. The water was a little on the cool side making my cock shrink a little. I swam to the deep end and sunk to the bottom before coming back to the top. I took my hand and wiped the water from my face and brushed my hair back. Once the water was removed from my eyes I saw Beth a few feet in front of me, smiling and I didn't know why.
"I'm glad you came swimming with me Daddy." She said. "I have a present for you, but you have to close your eyes first."
I agreed and closed my eyes, I heard a few splashes and when I opened my eyes Beth handed me first her bikini top then her bottoms. Her tits looked wonderful floating in the water and I could barely make out her shaved slit through the water.
"Don't you think this is a little risky?" I asked, "I mean you mom and sister are right inside the house."
"Well I am sure that Mom is asleep and I know that Julie will be busy at the computer for an hour. So as long as you don't make me scream I think we will be ok." Beth said smiling.
I just nodded and let my cock do the thinking. Beth reached out and pulled the string holding my swim trunks up and slid them down my legs. She moaned slightly at the sight of my cock in the water and moved a hand to stroke me. I moaned in response to her touch and soon I was thrusting in my stepdaughter's hand.
"My Daddy aren't you hard and ready quickly." She laughed.
I only smiled and reached out for Beth's tits and soon I was squeezing them gently in rhythm with my strokes. Beth moaned again a little louder and I moved us toward the shallow end of the pool. There the water was only about 3 feet deep and would allow me to do many more things to my little girl. My cock was almost out of the water now and I placed my hands on Beth's shoulders and gently pushed her downward. She got my meaning quickly and soon was sucking my cock. I can't begin to describe the feeling of her mouth while I was watching her tits sway in the water. Once again I began to thrust into her warm mouth and Beth just opened more to take all my meat into her mouth. I grabbed her hair and began to face fuck her harder. Beth continued to moan around my cock and took her free hand and pulled at her nipples while I fucked her pretty face. I felt my load rising and thrust deeply into her mouth as the first spurt of cum shot out of my cock I could tell Beth was smiling as I came in her mouth and she expertly milked my cock for every drop of cum. Finally my climax subsided and Beth let my shrinking cock slip from her mouth. She took her tongue and licked her lips and swallowed once more, not wasting my cum. I leaned in and kissed her lightly and Beth surprised me by stroking my cock again.
"Easy girl, give me a little time to recover," I laughed, "I'm not a young guy anymore."