Author's note: This is the final chapter in a four part story. If you prefer some buildup to the action and want to know the characters, read the other three chapters first. Otherwise, jump right in.
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On the morning of our last full day in Kalalau we were awakened by the sound of a soft rain hitting the fly of our tent. Everybody was still tired from the events of the previous day. I was still lying next to Birte and slowly stroked her back and butt, then worked my hands around to her front and played with her breasts for a while. I could hear the others in the tent stirring behind me. My hand slowly wandered down her belly and soon my fingers were playing in her pubic hair, giving it gentle tugs alternated with running my fingers through it. I parted her lips and could feel her excitement as a quiet moan escaped her lips and she rolled onto her back. I got up on my elbows and leaned over to kiss her. Our tongues softly explored each other's mouths and lips. After a couple minutes of making out, I spread her legs apart and positioned myself between them without breaking contact with our mouths. She reached up and stroked my cock playfully a few times, then guided me into her.
We got into a slow, rhythmic pattern where I would thrust into her and then gently slide out until we were almost separated but not quite. After a few minutes of this I looked around the tent and saw Sven making love to Michelle while Ann was being tended to by Leon. Everyone had big smiles on their faces. In a short while Leon was the first to speak when he said "I think now that everybody is warmed up and in the mood, its time to switch". I agreed and pulled out of Birte. I crawled up her body, slowly dragging my slick cock along her belly and across her breasts before stopping with it positioned right above her head. At that point I leaned over Michelle's outspread legs until my face came down inches from her pussy, where I stopped to savor the aroma before diving in. I felt Birte's tongue exploring my cock and balls as I lowered my mouth on Michelle's pussy. I explored tentatively at first, slowly running my tongue up and down her slit and gently nibbling on her clit. I turned my head sideways just enough to catch a glimpse of my wife taking Leon's large black cock into her mouth while Sven went down on her. Meanwhile, Birte had wrapped her lips around my cock and reached around me to place her hands on my ass and pulled me closer. I turned my attention back to the task at hand and penetrated Michelle with my tongue. That got her really hot because she grabbed my head with her hands and pulled it even closer. The tent was filled with the sounds of slurping and the smells of sex for the new few minutes as we all tasted our new partners.
Almost in unison, the men pulled away from their partner of the previous day and repositioned themselves above their new "wife" for today. Michelle had spread her legs wide apart and brought her knees up to her chest, giving me full access to herself. I plunged my shaft all the way in with one deep stroke and she let out a gasp of surprise. We slowly built up a rhythm of our own. Her legs were resting on my shoulders and my balls slapped her ass on each stroke. Out of the corner of my eye I could see Sven fucking my wife. Michelle and I increased our pace and intensity and soon I could feel her reaching her peak. I felt myself get close to the edge and I stopped my movement while I was deep inside her. I could feel her orgasm around me and that set me off too, as I exploded and released my load. As soon as we both caught our breath we looked into each other's eyes and smiled broadly before kissing for the first time. Then we watched the others wind down from their lovemaking too.
The rain had stopped, so I opened the tent door. It was almost as steamy outside as it was in the tent. We all dashed down to the ocean to cool off and wash the sweat and other fluids off our bodies. After we were done, Michelle and I walked hand in hand back to the campsite and began preparing breakfast. The others soon joined us and we all stood around naked eating our food. It was amazing how comfortable we had become with being nude together and it seemed so natural and comfortable as we discussed what to do for the rest of the day. Leon and Birte would visit the waterfall while Ann and Sven decided to explore the swimming pond. Michelle and I would stay on the beach. Today the others didn't even think about putting their clothes on as they prepared for their hike. We waved them goodbye and then grabbed our towels and sunscreen to head for the sand.
After about an hour of napping and soaking up the rays, we decided to walk down to the west end of the beach. But first we agreed that it would be wise to give each other a good coating of sunscreen to protect us for the full day of exposure. I had Michelle stand up while I coated her back and then her front. I knelt down to do her legs and ass, teasing her by sliding my hand between her thighs once they were all slicked up. When I was done, I gave her belly a quick kiss before standing up. Then it was her turn to do me, a task in which she took great delight. She spread an extra amount on my cock and balls, explaining "I don't want anything to burn that I'll be using later." I was hard again but nobody was close by.
We left our towels and walked down the beach along the firm damp sand as the shallow water lapped at our feet. After about a hundred yards we saw another couple approaching us from the opposite direction. When they got a little closer we could tell they were nude also so we relaxed a bit. We stopped to talk with them and found out that they were from Indiana. This was their fifth trip to Kauai and they hiked to Kalalau each time. They said they had been exploring the cave at the end of the beach and swum around the point to a secluded cove about 100 yards down the coast. We parted ways and continued on down to the cave. It was gigantic. The floor was lined with sand and we went so far in that the light from the opening was barely visible.
When we exited the cave, Michelle asked if I wanted to visit the cove. I glanced at the waves and they didn't appear too rough, so I agreed. We swam slowly, staying just a few yards apart. As we rounded the point, a beautiful white sand beach lined with palms came into view. We walked up the shore a little way and sat down. The wet sand felt cool on our naked butts. We talked for quite a while and then decided to get up. We waded out into the water to rinse off the sand and had quite a bit of fund helping wash the sand off each other's ass. I stood up behind Michelle with my now hard cock rubbing between her cheeks and reached around to play with her breasts. She turned her head to the left and I leaned over to kiss her. I took her hand and led her over to a rock jutting out of the water. She leaned over the rock and I got behind her again. Slowly we adjusted our positions so that I could enter her from behind. She was so slick that I slid right in. We moved tentatively at first, experiencing the novel sensations of a new position for us. Gradually we built up our tempo and our excitement increased. Every fourth or fifth stroke a wave of warm water would splash against our asses and private parts, adding to the total sensation. After a few more minutes we were at the point of no return. Michelle screamed loudly, taking advantage of our seclusion. I exploded inside her. Once we calmed down, we stood and faced each other, hugging and kissing in the surf.
It was then that we heard people yelling and clapping. Startled, we looked up and saw a sailboat just 200 feet offshore. It had snuck up on us quietly. It looked like there were about six men and women on board, and they were all naked too. We were totally embarrassed but we returned their waves with sheepish grins on our faces. As quickly as they had appeared, they changed course and sailed off, leaving us quite alone again. We finished exploring the beach and then swam lazily back to the main beach. Picking up our towels, we headed back to camp. Once there, I found a large hammock just off the main trail and we both climbed into it and fell asleep nestled together side by side.