Yosuga No Sora fanfiction based on the 1980 movie, "The Blue Lagoon": Disclaimer: I do not own Yosuga No Sora nor do I own "The Blue Lagoon". Yosuga No Sora belongs to Sphere and feel and "The Blue Lagoon" belongs to Columbia Pictures.

Chapter 2: Lustful Desires

Haruka & Sora Kasugano had been shipwrecked on a tropical desert island ever since they were both 9 years old. Many years later at the age of 16, they had both matured in body and mind. Both were wearing only small torn pieces of cloth that covered their nether regions. Haru had grown muscular and lean and Sora had developed small breasts but felt ashamed whenever she looked at them so she would cover them with her long silver hair. Haru was different. When he often glanced at his twin sister's small breasts even when she was bathing, he would easily get aroused and start to have an erection. They weren't as big as the breasts of the nude women in the pictures Mushin had secretly kept in his pocket, but Haru would often fantasize about touching them, even feasting on them.

One morning, Sora had just finished making breakfast. She cooked fish and crab meat and roasted lobsters. There were also mangoes, bananas, slices of coconut meat, and coconut milk to drink. She left the hut to search for herbs and plants to use for medicine. By this time, Haru had just woken up from his nighttime slumber.

"Where's Sora?" he wondered.

He got out of bed in time to discover the morning meal she made. He grabbed a slice of coconut meat and then took a mouthful.

"Sora did a very good job making breakfast," he thought. "I'll have to thank her when she comes back." Then he went to fetch his spear for hunting and the net to catch fish with. After getting the spear and the net, he saw that Sora had forgotten her bow and quiver full of arrows. "I've got to remind her to take these with her," he said. "Dangerous animals could be on this island."

Sora was busy collecting medical plants, then she saw the spiny amaranth. She took it in her grasp. "Mushin-sama said that this plant can cure venom from snake bites," she said. "I can brew it then mix it with coconut oil to use as medicine." Sora continued gathering various medicinal herbs and plants, oblivious to a slithering, unwanted guest.

Back near the hut, Haru was busy fishing in the lagoon. He lowered the net into the water. He searched the area for his twin sister, but there was still no sign of her. "She must be taking forever," he thought.

Sora had finished obtaining every herb and plant she could find about to head back to the hut when all of a sudden, "Sssss," hissed a sound. Sora stopped in her tracks. She always knew about the games and tricks her twin brother would often play on her.

"Okay, Haru," she called. "I know it's you. Come on out." There was no sign of him. "Ssssss," said the sound again. Sora quickly became nervous. Her heart started racing. "H-hhharu," she stuttered fearfully. "Get out of the bushes. It's not funny anymore." But it wasn't Haru. It was a huge python! Sora screamed in terror and dropped the basket. She was about to retrieve her bow and arrows, but she realized that she had left them in the hut! "Haru! Help me!" she shrieked.

Haru walked back to the hut after fishing. Suddenly, he heard Sora's frightened cries for help. "Haru! Haru!" He stopped in his tracks. "Sora! She's in trouble!" He dropped the net full of fish and ran to help the terrified girl.

The serpent hissed as it slowly slithered across the sand and stuck out its tongue. Sora was trembling frantically. Just when the giant snake was about to attack its prey, there was a bellowing scream. "Get away for her!"

Sora looked up. "Haru! You came!" she called cheerfully. Her elder twin brother had arrived just in time to protect her from the hungry python! Haru jumped in front of Sora and held up his spear ready to fight off the slithering predator.

"Go away! Leave her alone!" he bellowed lunging his spear towards the snake. It charged at the duo but Haru flung the spear towards the beast stopping it in its tracks. The python backed off hissing at the two and slithered away in defeat. Haru knelt on the ground, exhausted. Sora ran up to her brother and hugged him tightly.

"Oh! Haru!" she wailed. "Thank you so much for saving me."

"I told you I'd protect you," he replied. "I sensed that you were in danger. So I rushed to help you." He stood up. "Anyway, we'd better get back to the hut. It's too dangerous to stay out here." When he and Sora were about to return home, he felt a sharp sting from his right arm. He winced from the pain. Sora ran to her brother.

"Haru, are you all right?" she asked worried.

"I'm fine," he said. There were tiny drops of blood. "I must have cut myself while I was throwing the spear at the snake, but don't worry. It's not too serious." Sora examined the small cut. Then she ran to gather the fallen basket of scattered herbs and plants.

"Come on, Haru," she ordered. "Let's get back home before other wild animals try and attack us." Then she left with her basket. Haru went to retrieve his spear and followed his sister back to the hut.

Later that day after the twins finished eating the rest of their meal, Sora was busy applying aloe vera juice on Haru's right arm.

"Sora," said Haru.

"Yes," she replied.

"I want to thank you for making breakfast earlier today."

Sora blushed. "I thought I wanted to make something you like. I know I'm not that good at cooking, though," she explained.

Haru turned to her and embraced her. "Don't put yourself down," he told her. "I'll always like what you make."

Sora was euphorically surprised. "Thank you, Haru," she said kissing his cheek. Haru was stunned. She blushed once again. "Gomen ne," she whispered and walked outside of the hut. Haru followed her quietly. He peeked through the bushes secretly watching his sister swimming naked in a small pool near a waterfall. When she rose from the water, tiny drops of water rolled from her petite body. He started to feel his length harden.

Her delicate, milky-white skin shone from the faint light of the sun. Her breasts, her tiny perky nipples, her buttocks, every part of her seemed to be perfect to Haru. He put his hand on his erected pole under his small garment and began stroking it, imagining that he was touching her. He desperately wanted to claim her, even mate with her, but she was his sister. His flesh and blood. He knew that doing so was immoral and wrong. He quickly and silently crept away.

That night, the twins were having dinner. They ate roasted lobster, crab, and fish with mangoes, bananas, and coconut milk to drink. Haru wasn't eating very much. He was more curious than hungry. He had plenty of thoughts on his mind.

"Sora," he began.

"Huh," Sora answered as she stopped eating.

"Remember when Mushin told us that every full moon when there was a shooting star, we would make a wish?"

"Yeah, but none of those wishes we made ever came true. Mushin-sama was a liar."

Haru put his arm around Sora and sighed. "He even told us that if we ever dug far enough, we'd be able to reach China," he added. "And there was a pot of gold at the end of every rainbow, but there was no pot of gold after all," continued Sora. The twins both laughed.

The next day while Haru was busy catching fish with his spear and net, Sora went exploring and discovered a huge cavern with a large pool inside. She stripped off her clothes and dived into the warm water to go swimming. However, she stopped when she saw blood in the water. She lowered her hands into the water and then took them out to make absolutely sure. She was terrified!

"Haru!" she cried. "Help!"

Haru dropped his spear and rushed towards the cavern to help his sister.

"What's wrong?" he asked when he reached the cavern. Then Sora realized that the blood was coming from between her legs. She was menstruating, unaware that she had finally become a woman.

"You're bleeding!" gasped Haru.

"Don't look at me! I'm fine!" she warned.

"But you're bleeding," he agreed.

"I'm all right. Go away."

Haru began to back away.

"Go away! Just GO AWAY!" Sora yelled throwing a stick at him. Getting the hint, he left the cavern. She bowed her and cried feeling ashamed.

Later that day, Sora was sitting next to a small bonfire and tossing small sticks into the flames. Haru walked up to her. He sat down on a big rock.

"Sora, why were you bleeding like that back there?" he asked her.

"I don't know."

"Liar!"

"It's true. I DON'T know."

"Sora, people don't bleed unless they cut themselves," said Haru. "Maybe you're hurt real bad and you don't even know it." He got up from the rock attempting to inspect the bleeding. "Now come on. let me have a look." Sora moved away from him.

"NO! I don't want you to look, Baka," she protested.

"But why? he asked irritated.

"Just because."

Haru was irate. "That is not fair!" he hissed. "I don't keep ANY secrets from you. I tell you everything. EVERYTHING!" he stormed off in a huff. Sora saw him walk away angrily.

One afternoon, Haru was busy building a boat and Sora was watching him, dazed and bewildered. She stared at his muscular body: his abs, his pectorals, his wide shoulders. Haru stopped what he was doing and looked up to see his sister watching him. He got annoyed.

"What are you looking at?" he asked.

"Your muscles," Sora replied blushing.

"What about them?" he added looking down on his chest. "You're really acting strange lately, Sora. Always saying dumb things like that. Always looking at me funny. You're not coming down with something, are you?"

She shook her head.

"Don't give it to me," he finished and continued on the boat.

Later in the evening, Sora was playing in the water squishing it in different directions. Haru went outside to watch her. She splashed and giggled as the waves crashed into her. He was smitten by her beauty in the faint moonlight. She plunged into the water and started swimming. Haru joined her afterward. They both swam and played together underwater visiting coral reefs while many schools of fish swam past them. Their nude, blue silhouettes danced against the light of the moon.

The morning after, Sora gathered her medicine along with her bow and quiver full of arrows and set off to collect plants and herbs. When she was finished, she went skinny dipping in a nearby river. Haru, who had finished fishing, was in the hut lying in a hammock. He waited for his sister to return, but she never did. He knew he shouldn't be looking for Sora, but he was very overprotective of her. His sister complex was getting the better of him. He took his spear and went to search for his twin sister. When he finally arrived at the river, he saw her lying naked on her back on the banks touching and pleasuring herself. Once again, he felt his length in his small garment become erect. He began stroking it. He knew it was wrong to spy on his sister, but he could not resist the urge to watch her.

Sora continued pleasuring herself. She was caressing her breast with one hand and rubbing her wet holds with the other. Haru was losing his mind. He felt he should be the one touching her breasts. HE should be the one rubbing her moist holds. He became desperate. He no longer cared that Sora was his twin sister, his flesh and blood. He wanted to make her his and his alone. He started to stroke his length faster. He fantasized about his manhood penetrating her unexplored caverns. He fantasized about sucking her tiny nipples and feasting on her deliciously small breasts. All of her pleasures belonged to him. He wanted her to be his mate.

"Haru," moaned Sora touching herself. Haru was stunned! His sister had just called out his name! Was she fantasizing about him too? He slowly backed away from the bushes and headed back to the hut.

That night after returning from the river, Sora made dinner, but she wasn't very hungry. Haru was sitting next to the door. He had found out that his own sister was lusting for him just as he was lusting for her.

"Haru," she started. "I don't feel like eating tonight. I'm going to bed. You can have dinner if you want to." Then she climbed the ladder to the room she shared with her brother. Haru wasn't hungry either. He decided to skip dinner and head up to bed as well.

Later that night, Haru was lying on his side in bed, watching Sora sleep. She was topless but had her long hair covering her breasts. He was puzzled. They used to bathe together when they were younger, but ever since she had developed breasts, she would often find other locations to bathe.

The next day, Haru was sitting next to the table with his head lowered to his knees. Sora climbed down the ladder only to see her brother silently sitting near the table.

"Haru, are you all right?" she asked walking towards him. He refused to talk to her, he wouldn't even look at her.

"What's wrong? Why won't you talk to me?"

"Get out," he finally said.

"But, Haru... "

"I said GET OUT!" he yelled slapping her across the face.

Sora was shocked. Haru had never struck her before. She held her hand up to her face where he had just hit her. Tearfully, she yelled, "I'm not coming back, Baka!" and ran out of the hut.

Guilty about what he had done, Haru ran after her.

"Sora!" he called.

"Don't talk to me!" she screamed racing away.

Haru kicked the sand. "Dammit!" he hissed. "I didn't mean to hurt Sora. I just wanted some time alone. I'll have to apologize to her when she comes back."

Somewhere in another part of the island, Sora sat on a large rock looking in the direction of the ocean. She was crying. She was angry that Haru had kicked her out of the hut.

"Baka Haru!" she wept. "Baka! Baka! Baka! Baka!" she blurted out pounding her fist on the rock repeatedly. "Baka Haru! I'll never return to him. EVER!" She stood up and kicked the water. A small jellyfish, that was swimming in the water, stung the girl on her foot. She shrieked in pain and slowly backed away from the water.

Later that day, Haru was waiting for Sora to come back so he could apologize for throwing her out of the hut due to his nasty behavior, but she never showed up.

"What's taking her so long?" he thought. "She's never been away this long." He got this spear and went out looking for her. "Sora! Sora!" he called. There was no reply. There was no sign of her. "I'm really worried about her. I have to find her and bring her back home." Then he paused. He saw his sister lying on the sand. She was clutching her foot and wincing from the pain.

"Sora!" he screamed running towards her.

"Go away," she murmured in agony.

"No! I'm not going to leave you," he protested kneeling next to her. "What happened?"

"I got stung by a small jellyfish," she told him.

Haru was frantic. He knew he had to help his twin sister or he'd lose her forever. He helped Sora climb on his back and carried her all the way back to the hut. By the time they finally got back, Sora's foot was throbbing. She was groaning from the intense pain. Haru had never been this worried before. After climbing up to the room they shared, he placed her down and then laid her on the bed.

"Sora. Please tell me what to do. How can I cure the jellyfish sting?" he asked.

Sora could not speak due to her having difficulty breathing, but after a while, she mustered up all of her strength to whisper, "Star fruit, pineapples. Extract the juices and mix them together." Haru nodded. "Get some salt water to stop the sting. Then boil some water, and make it hot enough to stop the venom," she added.

"Okay," said Haru. He did everything Sora had instructed him to do. He collected star fruit and pineapples for the juices to make the medicine. Then he collected water and boiled it to use for Sora's foot. He gave her the medicine he made and dipped her foot in salt water to halt the sting. Then he carried the cauldron up to the room and placed her throbbing foot into the hot water to deactivate the proteins in the jellyfish venom.

Haru was watching his sister. She was unconscious and sweat broke out from her petite body. He wiped it off with a damp cloth. He carefully cleaned her naked body. He moved her long hair to wipe her breasts. It was the first time he had ever seen them up close! They were perfect! Every part of her petite was perfect! He had a sudden urge to touch her but continued cleaning off the sweat. He moved to her private area when his manhood quickly became erect. He shook those lewd thoughts from his mind and kept wiping her.

That night, Haru kept his eyes on Sora. He took her hand and moved it closer to him.

"Sora," he whispered. "Please don't leave me. Please don't go to sleep and not wake up." he began to cry. "I promised that I would protect you," he said sobbing. "Please open your eyes. I need you. I love you." He kissed her hand.

The next day, Sora had awakened from her deep slumber. She saw Haru laying his head beside her. "Haru," she mumbled. "Is that you?" Haru opened his eyes. He was relieved to see his sister awake.

"Yes, it's me," he answered happily. "I was so worried about you."

"You mean you're not mad at me anymore?"

He shook his head. "I'm sorry about the way I acted to you yesterday. I promise to never abandon you again. I want you by my side. I vow to always protect you from now on. You're the only thing I have left in this world. I wouldn't know what to do if I had lost you."

"Haru," Sora said through watery eyes. "I'm the one who should who should apologize. I'm really sorry that I said those hurtful words to you."

He placed his finger on her lips. "You don't have to apologize," he told her. "Just lay down and rest a little bit."

Later, he climbed down the ladder and went to fetch the meal she cooked a couple of days ago. He went back up and brought it to her. "Here's some food to help you get your strength back," he said.

She ate some. "Aren't you going to eat too?" she asked. He shook his head. "No," he responded. "I've already had some." She continued.

Haru looked out to the sea.

"Sora," he said.

"Yeah," she answered and stopped eating.

"When you're done with your meal, I want to go swimming with you."

"Really? You do?"

"Yes,"

She was so happy, she felt tears in her eyes. "All, right." After Sora was done with her meal, she climbed down the ladder with Haru's help.

The twins went swimming in the lagoon for a long time. They swam past fish, turtles, and other sea creatures. Then they rose back up to the surface laughing and heading back to the shore.

To be continued...