The people in the story are all over the age of eighteen, the age of consent. Sex is mutual and consensual. This is a work of fiction and the timescales and narrative belong to my world not that of reality.
*****
"Shit!"
David Jones stared at the small dinghy bobbing way off in the tide.
"Dave, what's happened?"
Sarah his sister looked out to sea,
"Oh No! Dave I thought you tied it down?"
"So did I, bugger!"
"Well swearing's not going to get it back, can you swim out to it?"
"Not really. it's on an ebb tide, as I swim out it's already going to be further out. Unless I can swim faster than the tide, we're stuck."
"Please try, we can't stay here."
Sarah sounded desperate so Dave walked into the waves and dived in the direction of the dinghy. Twenty minutes later he stumbled ashore and was helped out by Sarah.He lay on his back on the sand, exhausted, breathing heavily, his chest rising and falling as he gulped in the air. He coughed and rolled over, vomiting into the sand.
"Sorry, I'm really sorry."
"Don't worry, you really tried, I watched you."
"Yeas but I lost the boat."
Look it's okay, we've got some water and a few snacks, we'll get it sorted."
Dave sat up and Sarah helped him to his feet. He was still breathing raggedly. They walked slowly up the beach to the palms that fringed it. Between two giant trees lay a couple of towels and a beach bag. Reaching in Sarah pulled a fresh sealed bottle of water out, passing it to him. Dave had a few swigs then passed it to Sarah. She drank slowly and then passed it back. Dave tipped the bottle up and gratefully swallowed. They sat on the towels watching the waves and feeling a slight cooling breeze.
They had arrived three days before with their parents for a last family summer holiday before Sarah left for University. Dave was in his final year but they knew this was the last time for a while they would all be together. She was nineteen, he twenty three, he was at Durham, she would be going to Plymouth almost the opposite end of the country. They were enjoying the Caribbean resort holiday, and had decided to hire a small powered dinghy and explore the numerous small islands around the main island. Now they were stuck, probably overnight, possibly longer. For once in their lives they had not bothered to take their mobile phones, since reception was patchy, so they had abandoned them in their rooms. Now they had no way of letting their parents or the hire people know where they were or what had happened. They sat side by side gloomily staring out to sea.
"I need to pee," Dave stood to move into the strand of trees.
"Wait where are you going?"
"Off to pee, why?"
" Well I don't want to be here on my own."
"A minute! Two tops!"
"I'm frightened."
"Look I need to pee, the place is deserted, you'll be safe here."
"No! Please don't go, please."
"OK, turn your back to me,"
"What?"
"Turn round, so I can pee."
"No, you'll disappear, just go,"
"I can't!"
"Why not?"
"Because!"
"Because what?"
"You're my sister and I can't just get my dick out in front of you."
"Why?"
"Because, you're my sister and I don't want to flash my dick at you."
"Why is is it super small or super big?"
"No! it's just..."
Oh for Gods sake, just do it, I won't look, but stay by me okay?"
"Shall I hold your hand?"
"As long as it's not the one you hold your dick with."
"Ha Ha funny."
"Well go on then! Get on with it!"
"Right,"
Dave fished his cock out of his shorts and holding it away relaxed his bladder muscle. A few splutters came out before it sprayed out with force creating an arc of pee back towards the sea.
"Oh wow, that's impressive, does it always go that far."
"Are you watching me pee?"
"I certainly am, and I'm glad I did, not only is that an impressive cock brother of mine, but a big, big piss."
"You shouldn't be looking."
"No I shouldn't but I'm glad I am, oh is that it?"
"Yup, show's over, now do you mind if I put it away now?"
"If I said no would you leave it out?"
"No!"
"Well no sense in asking then, my turn."
Dave watched in amazement as his sister faced him, pulled her shorts and bikini bottoms down and squatted in the sand in one smooth movement. A soft hiss and a stream of pee hit the sand, bubbling and disappearing, leaving a wet patch.
"Well that's hardly fair, I couldn't see anything."
"Those are the breaks Bro."
"Whatever, we need to have a walk round this place, in case we can find... something."
Sarah stood, hauling her bottoms and shorts up together, with a practised wiggle she had everything back and buttoned up, without Dave seeing anything.
Dave bent and picked up two of the empty bottles they had and Sarah picked up two more, she stuffed them in the empty beach bag with the towels and offered it to Dave to do the same. He threw the bottles in and Sarah closed the bag and put the straps over her shoulder, tucking the bag under her arm.
"Right we're all finished here, okay let's walk back through the trees. Come on!"
Dave grabbed Sarah's hand and yomped off in between the trees. They were on a gentle rise, soon the trees gave way to a grassy upland. This thinned out to a few rocks until the slope plateaued out at about thirty metres above the beach, a flattened ridge ran along the island's top, sloping gently back down to trees and a beach all around. There were no trees at this level, no animals, no birds. About half way along the ridge the level dipped producing a small pool, about six metres long and three or four wide. , the water was clear and a small cleft slightly above the water level, showed that this is where any overflow drained away.
Dave knelt by the water and smelt it, it didn't look or smell brackish, there was no growth on it. He dipped a hand in and sipped the water. It tasted all right. He nodded to Sarah, who likewise ran a scooped hand just under the surface and drank the resultant scoop, slowly, enjoying the coolish taste.
"Hmmm, well let's fill the empty bottles we've got, that will give us fresh water overnight. then we'll see what tomorrow brings."
They filled the bottles and continued past the pool, and checked the island for any other signs of life. It soon became apparent that it was deserted. Sighing Dave helped Sarah down the slope and they emerged on another beach like the one they left. They kicked off their shoes and walked barefoot over the hot sand. Sarah stopped and removed her shirt, revealing the matching bikini top for her bottoms. Her firm breasts filled the cups perfectly. Even after a few days her skin was tanning beautifully. Grunting Dave pulled his shirt off and they put them in the bag. Dave took the bag held his other hand out to his sister. She grabbed it and they walked together.
"So, what now Robinson Crusoe?"
"We settle down and keep warm, then start again tomorrow.
"Come on we can't be that far from civilisation, can we?"
"Well we motored for about an hour and a half, so I guess there must be something just over the horizon."
"OK, what about when the boat drifts into view, that'll start them searching won't it?"
"Yes, I guess, but unless we can get a fire started to attract attention, they could take a while to find us."
"A couple of hours maybe?"
"Possibly or a day, not more than that I wouldn't think."
"Great! So I'm marooned on this tiny little island, with no food, some water and nowhere to sleep."
"Yup, with me for company."
"This sucks so much."
"Bite me!"
"OK, can we start a fire?"