Mark & Jennifer had been looking forward to this vacation. Their uncle had been planning a trip up the east coast of Africa. Mark, just 18, a handsome young man, and his gorgeous, dark-haired 19 year-old sister Jennifer were to join him. They'd been packing for a month in anticipation of the trip. They were going over land up the coast, at least as far as Zanzibar, and would then have to turn back in time for the new college semester. They had finally left their home on the East Coast, and started their expedition. They had spent two weeks on the road before finally reaching their destination, and were camped on the coast of Zanzibar when disaster struck!
They'd rented a large canoe to explore the Islands that litter the coast off Zanzibar, when one of Africa's late afternoon thunderstorms hit. It tossed their canoe around madly, throwing all three of them into the water. Mark and Jennifer struck out for the nearest land, and after an eternity of hard swimming, they collapsed on the beach.
When he came to, Mark slowly raised his head. He saw his sister Jennifer lying a meter or two from him, exhausted, wet, but alive. Their uncle was nowhere to be seen. They wandered the beach until it got dark, looking for their uncle, to no avail.
Mark headed back to where they had first landed, and stumbled across one of their waterlogged backpacks, which had washed ashore. Mark emptied it and found a water canteen, a Swiss army knife, and a first aid kit. Better than nothing, he thought. Jennifer was crying nearby.
"We'll be alright. I promise," he said.
"I'm just so scared Mark," she sobbed back at him. "We're all alone, and Uncle Terence is missing!” She broke down again.
He held her close, comforting her, feeling her large breasts against his body.
"We'll be alright, Jenny - at least we're alive."
Mark constructed a lean-to shelter for them to sleep under, while Jennifer furtively scanned the sea for sign of other boats.
After a couple of weeks, both teens had given up on a quick rescue. Their parents weren't expecting them back for weeks, and there were dozens of islands in the area. They fell into a routine of collecting fruit and water, resting in the hot, tropical afternoons, and taking turns at watching for boats.
By this time too, they'd started to recover from the initial shock of their ordeal, and were struggling to adapt to their new circumstances. Mark's young beard started to grow, much to the delight of Jennifer, who teased him about it.
Two weeks in the wild without her Lady Bic razor had left Jennifer with a very full bush that peeked out from her bikini, and crept down the inside of her thighs in a rich, dark auburn. Soft, downy dark hair appeared on her legs as well. As for her armpits, what had started as dark, peppery stubble was now thick tufts of luxurious dark hair. She only had one T-shirt to cover her bikini, and even when she wore it, one could see a dark shadow under her arms.
None of this was lost on Mark. He had noticed the lush, dark hair under his sister's arms, and the curls around her bikini. He had always known that his sister was attractive, and had always enjoyed stolen glances at her large, full breasts. Here, hey were less shy about their bodies around each other, and every time he caught a profile of his sister’s big, soft tits (he had yet to see her nude) and hairy armpits, he felt his cock stiffen, and inevitably had to rush off into the bushes to stroke himself while he imagined running his hands all over Jennifer’s hairy body.
Mark awoke one morning with a raging erection, and was about to go and do something about it when he noticed that Jennifer was already awake. Her eyes were transfixed on his crotch, which throbbed noticeably through his worn out shorts.
She slept close to him, so she had a good view of his hard-on. She had raised herself up onto one elbow to get a better look, and he couldn't help but notice the dark hair in her armpit. This made his cock throb all the more. Her breast was spilling out from her ragged bikini top, and he could see the pink glow of her areola.
Jennifer suddenly noticed that his eyes were open, and where they were focused.
"Ohh! Ohh, Mark...I didn't..." she gasped as she wrenched her gaze from his erection, embarrassed both by what she’d seen, and by what he'd been looking at. She quickly closed her arm against her side and looked away in shame.
