Komaru eagerly stood by the door, waiting for Makoto to arrive home for Summer break. She had been waiting all day to see him again, and she could barely contain her excitement.

There was a reason for her excitement besides just seeing her brother, though.

After her brother had gotten lucky and got accepted into Hope's Peak as the Ultimate Lucky Student, she had become so proud of him, and it started to make her realize how much she loved him. Things only escalated from there.

The more she thought about him, the more she couldn't get him out of her head, and it all built up to when she found one of his hoodies. She hugged it to herself, and for some reason, started smelling it. His scent was still on it, as weird as that sounds. She couldn't stop herself once she started, and before she knew it, she had a hand in her panties, and her finger was roaming over her crotch. She ran to her room and masturbated while holding the hoodie.

After that, anytime she started thinking of him, she grabbed the hoodie and masturbated with it. The more she did it, the more she thought about him, and the more she wanted to see him. That's why she was eagerly waiting for him more than she usually would have.

A smile appeared on her face as she heard footsteps approaching the door, and when the door opened, she lunged, tackling Makoto to the ground.

"Ow...K-Komaru, why did you do that?" he asked as she layed on top of him.

"Because I'm happy to see you!" she said as she hugged as they were still on the ground.

"That's great and all, but can you let me get up first?" he asked with a laugh. She got up and waited for him to get to his feet before she wrapped him in another hug, and he hugged back. He grabbed the bag that he had with him and headed inside, where Komaru closed the door behind them. Their parents came in and hugged him, welcoming him home and asking him about the school, where he promised to talk to them about it over dinner. Once their parents finally relented, their mom went into the kitchen to cook dinner early so they could hear about the school, and their dad went into their parent's bedroom to continue working on something. Once they were gone, Makoto sighed and sat down on the couch. Komaru smiled again and sat next to him, giving him a moment before she hugged him again.

"Why do you keep doing that?" he asked as he hugged back again.

"Because I really missed you, duh!" she said as she pulled away. He laid back and sighed again. "You look exhausted."

"It's the people." Makoto explained. "They're amazing, but they can be a handful." Komaru giggled.

"You sound like a teacher talking about her students." she said, and he laughed, closing his eyes. Komaru laid back and watched him. Despite how exhausted he looked, he also looked peaceful. He also seemed to be a little taller, and maybe even a bit bigger, like slightly more muscular.

As her eyes roamed down his body, they eventually landed on his crotch. She didn't know why, but her eyes wouldn't move away, and, just for a moment, she wondered what he looked like underneath his clothes.

She gasped and blushed as she looked away from him. What...why did she think that?!

"Komaru?" Makoto said, making her jump. "Are you okay?"

"Y-yeah!" she said quickly. "C-can I turn on the TV?" she asked, and he nodded, closing his eyes again. She turned on the TV and changed it to a random anime to try to take her mind off the thought she had had.

"Reminds me of Hifumi already." Makoto mumbled.

"Huh?"

"Oh, nothing." he said. She shrugged and turned her attention back to the TV, but couldn't really focus. After a while, their mom called them in. The meal was Makoto's favorite. They sat down, said their thanks, and Makoto took one bite before he noticed everyone staring at him. "Oh, right." he said, and started telling them about Hope's Peak, how the school was, how the classes were, how the teachers were, and then he started talking about his classmates. AS he talked about them, Komaru became more and more amazed. When he got to a certain person, she gasped.

"You were classmates with Junko Enoshima?!" Komaru asked. "The fashionista?! The one on the magazines!?"

"Yeah." he said with a smile. "She's really nice and actually has a sister."

"That's so cool!" Komaru exclaimed. She let him continue talking about the rest of his classmates, every one of which seemed cool. When he finished, she swallowed her bite and asked the question she had been thinking earlier.

"Did you work out?"

"Oh, well, yeah." he said with a nervous laugh. "Between Mondo, Hina, and Sakura, I got roped into doing exercise quite a number of times."

"Well, you look good!" she said, and he smiled. She took a sip of her water.

"So, did you meet any 'special' girls?" their dad asked suddenly, nearly making Komaru spit out her sip.

"Th-that's…" Makoto stuttered as he turned a bit red.

"Oh, leave him alone honey." their mom said, and their dad laughed. For some reason, Komaru was suddenly filled with jealousy and anger. She shoved those feelings out of her head and kept eating as Makoto kept describing his time at Hope's Peak.

After the meal, Komaru did the dishes, then joined Makoto back in the living room on the couch, watching TV until it was time for Komaru to take a shower.

She walked into the bathroom and stripped down, setting her clothes aside as she stepped into the shower, closing the curtain. She referred a shower over a bath any day. She turned on the water and set it to the perfect temperature before she turned the shower head on. She grabbed the soap and started cleaning herself. As she ran the soap over her body, her thoughts began to wander, drifting to Makoto and his reaction to their dad's question.

She was so lost in thought that she didn't notice the door open and someone enter until the curtain was pulled aside. Komaru turned to see Makoto looking away, his entire face red. She screamed and rushed to cover herself as Makoto ran out of the bathroom, yelling. "I'm sorry! I swear I didn't see anything!" Komaru blushed and closed the curtain, wondering how he had possibly not noticed.

The blush didn't leave her face as she kept thinking about it, wondering if he had actually seen anything. Had he seen her breasts? Or maybe...her crotch? Before she realized it, her hand was once again at her crotch, and she started running a finger over her clit as she thought more and more about if he had seen anything. She moaned quietly as she rubbed her pussy, blushing. She reached up and gingerly grabbed onto her breast and started squeezing it, moaning a little louder. She gasped as she stuck a finger inside herself and started thrusting it in and out. She moved her fingers and pinched her nipple, making her moan even louder. The fact that he may be able to hear her moans made her feel even more aroused, and she shuddered as she came, cum shooting onto her hand. She panted as she washed off her hand and finished showering. She stepped out, dried herself off, and wrapped the towel around herself before she walked back to her room. Komaru got her pajamas before she heard a knock on her door. "Yes?" she asked.

"It's me." Makoto said. "Can I come in?"

"Yeah." she answered, and sat on her bed as he opened the door and walked in, blushing a bit at the sight of her in a towel. He bowed.

"I'm sorry, I was so lost in thought that I didn't even notice you were in there." he said. "I swear I didn't see anything."

"Makoto, it's fine, really." she said. "It was an accident, though you really should pay more attention. It's okay." He breathed a sigh of relief. She smiled and stood, walking towards him with her arms outstretched. He backed away, shaking his head as he glanced down. She remembered she was in a towel and laughed. He walked back out, and she got changed. She went back and told him goodnight as he walked into the bathroom, then headed back to her room and got into bed.

As she laid there, the day's events ran through her head. She couldn't stop thinking about how aroused she had gotten at the idea of him seeing her body. She hadn't realized it before now, but she wanted him to see her body.

She closed her eyes as she decided on what she would do tomorrow.

Their parents walked out, saying they'd be gone all day, just like Komaru knew they would, so once they left, she told Makoto she'd be out doing some stuff, and left.

She went to a store and bought some clothes, blushing as she paid for them, then headed back home. She walked back to her room, seeing Makoto watching TV on the couch. She quickly changed into the first outfit she bought, though it could barely be called clothing.

"Hey, Makoto?" she said as she walked out. "I'm probably going to the beach this Summer, so I bought a swimsuit. What do you think?" She stood in the living room, and he turned to her for a only a moment before he looked away, blushing.

The swimsuit was the most revealing thing Komaru had ever worn. The bikini barely covered her nipples, each part being maybe three centimeters, and the bottom was hardly much bigger. The back was almost riding up into her ass.

"I-I-I…" Makoto stuttered. "Th-that's w-way too revealing!" She nodded, enjoying his embarrassment as well as her own.

"Alright, good to know." she said. "I have something else I want you to look at, though." She walked away, giving him a view of her ass as she did. She changed into the next outfit and walked out. He gasped as he saw her.

"I was thinking of getting a job at a maid cafe." she said as she presented the black and white maid outfit. He stared at her for a second before he smiled.

"You look really cute in that." he said, and her heart skipped a beat, causing her to forget what she had been planning to do. She forced her thoughts to return before she lifted the skirt as she bowed. She turned and, with a deep breath, let herself fall to the floor, her skirt flying up.

"Ah-!" Makoto exclaimed and quickly looked away from her bare ass. She had left her panties off to pretend to trip. "Wh-why aren't you wearing any...any…" Komaru giggled to herself quietly. He couldn't even say the word.

"Oh. I guess I forgot them." she said as she stood. "Sorry."

"Again, I swear I didn't see anything, but how do you forget something like that?" he asked. There was no way he hadn't gotten even a small look. He may have even saw her pussy. That thought made her twitch, so she stood, brushed herself off, and walked back to her room without answering his question.

She took off the outfit, put on a bra and panties, and slipped on a see-through nightgown. She took another deep breath and walked back out into the living room before sitting next to Makoto. He looked over at her and leapt back.

"Komaru! I can see your...your underwear!" he said, blushing again. She had never seen him blush so much before and she was loving it.

"It's fine." she said, and he just stared at her, open-mouthed.

"O-okay…" he said, and slowly settled back down, turning back to the TV. She noticed that he kept glancing over at her, and she was surprised he had let it go so easily. It wasn't enough. So she reached behind her back and started undoing her bra, making Makoto gasp and blush even more. She removed her bra and threw it aside.

"Komaru!" he yelled again, closing his eyes. "I can see your ch-chest!"

"It's fine." she said again as she started crawling over to him. "We're siblings, after all."

"That makes it worse!" he exclaimed, and gasped as he felt something soft press against either side of his arm. He opened his eyes to find her grabbing his arm, which was beginning to go in-between her breasts. He tried to maintain eye contact to protest as she pulled him closer and closer.

He finally gave up and leapt away from her, running to his room and closing the door. Komaru smiled and crept after him, putting her ear to the door. She heard him panting on the other side, and she wondered if he would masturbate.

Her next "outfit" wouldn't be in use until dinner, so she crept to her room, where she threw off the gown and panties and put Makoto's hoodie on over her nude body. The hoodie still smelled like him. She went back to the living room and sat on the couch. She smelled the hoodie again, and while thinking about what had happened in the past few minutes, she started getting hot down below, so she lifted up the bottom of the hoodie and started fingering herself. She moaned his name a bit as she touched herself.

She didn't notice Makoto watching her, seeing the back of her head as she masturbated with his hoodie. He could feel his erection growing, one that had started when his arm was between her breasts. He ran back to her room, confused.

Meanwhile, Komaru climax with a gasp onto the couch. She went into the kitchen and grabbed paper towels to clean up the mess before she sat back down, waiting for dinnertime.

Makoto sat on his bed as he read a book, trying to get that image of Komaru out of his head. Something was up with her, but he wasn't sure what.

"Makoto! Dinner!" Komaru suddenly called. He looked over at his alarm clock. Where had the time gone? He sighed, marked his place, and walked out of his room to the kitchen, stopping in his tracks when he saw Komaru by the stove.

Wearing nothing but an apron.

This time, Makoto's eyes locked onto her ass. It was smooth and pale, and he couldn't help but stare at it for a few glorious moments before he turned away. "Why aren't you wearing clothes?!"

"Oh!" she said, and turned around. He turned back to her, figuring it was safe to look, but gulped as he saw a bit of the side of her breasts popping out from the side of the apron. "I...usually do this when I'm alone, but I guess I forgot." she explained, and it was then that he noticed her nipples poking out from under the apron.

"Komaru, what is going on?" he asked.

"Nothing. Here." she said, turning to grab the food and giving him another look before she turned back around with a bowl in her hand. He walked up and hesitantly grabbed it, trying not to look at her cleavage.

"Why have you been dressing in...revealing things all day?" he asked, deciding not to mention her masturbating.

"It's just some coincidences. Sit down and eat." she insisted. He opened his mouth, but she shook her head and moved to pull out his chair. He sighed and sat down with his food, said his thanks, and started eating as she sat down, doing the same. The meal was silent, and when they were done, Komaru collected the dishes and started cleaning them. Makoto tried not to stare as she shook her hips and hummed while she cleaned. He moved to the living room and sat down with a deep sigh, turning the TV on and to a random channel. He noticed her finish, and didn't look at her as she walked past him and went to her room. Soon, he heard the shower running, and he let out a sigh of relief.

The shower didn't last long, though, and soon, he heard Komaru return to the living room in her towel.

"Hey, Makoto?" she asked, and he looked over at her. "Can I ask you something?"

Before he could answer, her towel fell down, and he stared for only a moment at her nude body before he closed his eyes, his face turning red. "Y-your towel!" he yelled, but she just giggled.

"It's fine." she said. He was getting tired of hearing that. "In fact…" Suddenly, she grabbed his hand and moved it. He gasped as it came in contact with something soft and round. He jumped away.

"Komaru, what in the world is going on?! What are you doing?!" he yelled, still keeping his eyes closed. "You've been trying to show me your body all day! Why?!" She took a second to answer.

"S-sorry."

She spoke those words quietly before she ran back to her room. He sighed, opened his eyes, and sat back down. He didn't really pay attention to the TV, though. After a few moments, he decided to take a shower and head to bed early.

Komaru watched him through a crack in her door, and when he went into his room, she closed it.

Later that night, Komaru tossed and turned, unable to sleep, unable to stop thinking about how good Makoto's hand had felt on her breast. She knew he was upset, but despite that, she couldn't stop the thoughts from coming in.

The lust she felt was enough to get her out of bed, and she crept down the hall to his room. She opened the door slowly, stepped inside, and closed the door behind her. She could see him sleeping peacefully in the moonlight coming from his window. Ideas flooded her head as she stared at him. She knew what she wanted to do was wrong on so many levels, but she couldn't stop herself as she walked towards him. She stood next to him and watched him for a bit before she realized how creepy that was. She looked down at the blanket covering his body, and before she could hesitate, she pulled it off of him onto the floor. He was in some simple clothes, a white shirt and blue shorts. She could see boxers poking over the waistband, which was unlike her, who slept without a bra and sometimes without panties when it was hot.

She took a deep breath and hooked her fingers into the waistband of his shorts and boxers and started pulling down. The first thing to show up was his pubic hair, which already sent her heart racing. She continued until something that seemed to be pink appeared. He froze, took another deep breath, and in one motion, pulled them down the rest of the way, pulling them off his feet and throwing them aside before turning back. She covered her mouth with a hand as she gasped.

She stared at his flaccid penis, which was bigger than she would have expected. She could see his veins underneath the skin, and the head was nice and pink. Komaru's heart beat a mile a minute as she reached out and gingerly grabbed onto his dick, making it twitch. She moved it around to look at it all, not being able to see it that well in the moonlight. She looked lower to see two sacs underneath. She grabbed one with her other hand and rolled it around a bit before she returned her attention to his actual dick. The head had a small slit in it, which she ran a finger over, making it twitch some more.

She didn't have any actual experience with this stuff, but she knew what to do. She climbed up onto the bed, leaning over him. She looked down at his dick and bent down. She grabbed onto it again and planted a single kiss on the tip.

Once again, it twitched, as did Makoto's face. It was rougher than she expected. She leaned down and kissed it again. Then again. And again. She planted kisses all over his head before she moved down to the shaft. While it was softer there, it was beginning to harden. She continued kissing it as she fondled his balls. His face continued twitching. She moved back to the head and started to suck on it, making him moan. His moan made her shiver, so she pulled away, and pulled down her pants and panties and, after a moment of debate, she decided to take off her shirt as well, leaving her nude and even more aroused.

She moved back to him and started licking his shaft, which made his knee bend, sending it straight against her pussy, making her moan. She started moving her hips back and forth, spreading her pussy lips against his knee. She was already wet, so her wetness was sliding all over his knee. She grabbed his dick again, and began to suck on it again, making him moan again. She continued moving her hips more as she pushed his now fully erect dick deeper and deeper into her mouth, until it was fully in her mouth, making her gag a bit at first. Makoto gasped and moaned, somehow still asleep.

She accelerated the movement of her hips even more as she sucked on his dick, wrapping her tongue around his shaft, feeling his veins pulse under her tongue and his entire dick throbbed. She was moaning through his dick as she felt pressure growing in her crotch, until she cried out as she climaxed, shooting her cum onto Makoto's knee, still blowing him.

Suddenly, Makoto's eyes shot open, but before he could say anything, he moaned and cried out as he too climaxed, filling her mouth with his seed. She swallowed it as it came out, making sure to get every drop before she pulled away with a smile and wiped her mouth. Her smile fell when she saw Makoto's face, though.

"K-Komaru! Why are you...why are you naked?!" he exclaimed, before looking down, covering his penis with his hands. "Where are my pants?! What the hell is going on?!" She cringed. She knew it was bad when he said any sort of curse word.

"I...I, um…" she stuttered, trying to think of an excuse, but then she blurted out her realization. "I love you!"

"I know, but-"

"No, I mean I LOVE you!" she exclaimed, and he froze. "I...I was so proud of you when you got accepted into Hope's Peak, and it made me realize how happy I was to have you as a brother." As she continued, she felt tears forming in her eyes. "I admire you so much, and you've always been such a good brother, and a good person, and I realized...I realized I wanted to be more than your sister, maybe, and that...I was in love with you. It's weird, I know, but…" She was rambling now as tears fell down her cheeks.

"Hey, it's alright." he said, trying to reassure her.

"No...sisters aren't supposed to fall in love with their brother, and want to have sex with them." Makoto went wide-eyed at that, but she continued. "It's wrong, and…" Suddenly, she stopped as he wrapped her in a hug. The tears kept falling as she hugged him back, burying her face in his shoulder.

"It's fine." he said, as she laughed.

"Throwing my words back at me, huh?" she said, and he laughed as well. "What...do I do?"

"What do you want to do?" he asked, and she blushed as she thought about all the lewd things she wanted to do, so she decided to say something tamer.

"I want to kiss you."

"Then do it."

She moved away from him and looked at him with shock. "Wh-what?"

"I want you to be happy, Komaru." Makoto said as he wiped the tears from her eyes. "If that's what would make you happy, then...I'd...I'd be willing to try…" he said, and blushed. She stared at him for a moment before she hugged him again. After a few moments, she pulled away and they stared each other in the eyes. She started leaning in, closing the distance between them. He closed his eyes, and she did soon after, continuing to move forward until their lips touched.

His lips were surprisingly soft and warm. She pressed hers onto them, and he pressed back. Other thoughts began to flee her head as she felt herself melting into the kiss.

She reached behind his back with one hand as she grabbed the back of his head with the other and pulled him closer. He let her, and she poured all of her pent-up emotions into the kiss.

She moved her hand from behind his back and grabbed his hand, placing it onto her breast again, making them both gasp. He broke the kiss then. "Komaru-!" But she kissed him again before he could say more. He gave up and gave it a squeeze, sending a jolt of pleasure through her body. He moved it around as he squeezed it. She moaned and moved her hand back to his back, and pulled him forward, leaning back as he fell on her, breaking the kiss as his head landed between her breasts. She leaned up to his ear.

"Suck on my nipple." she whispered, and he looked at her with wide eyes. She could see the hesitancy in his eyes, but she just smiled. He nodded and moved down, dragging his penis down her leg, making her shiver more. He leaned down, but before he put his mouth on her nipple, she grabbed his arm, stopping him. He looked up at her in confusion as she grabbed the hem of his shirt, pulling it up and off of him. "There." she said as she stroked his chest. He laughed, and moved back down. He gently put his mouth over her nipple. She moaned again as instant ecstasy ran through her, which only increased as he started flicking his tongue over the hard nub. He grabbed onto her other breast and squeezed it rougher than before as he licked her. She grabbed his head as he moaned, which made him switch to sucking on it, making the breast move around. She felt herself getting wet again, and she wanted him inside of her.

"M-Makoto-!" she cried, and he finally pulled away from her nipple. "P-please! Put it in!"

"Wh-what?" he asked. "But...you can only lose it-" he didn't have time to finish before she shoved him onto his back and crawled over him. She looked to see that his dick was fully erect again. She positioned herself to where the head of his dick pressed against her wet pussy. "W-wait!" Makoto pleaded. "I-I don't think we-" But it was too late, as she lowered herself, and his dick entered her.

She cried out in pain as he went in, especially as he broke through something inside her, but kept going until he was fully inside her. They sat there for a bit, breathing heavily. She laughed, and he looked at her in confusion.

"I wasn't expecting to have sex with my brother when I woke up this morning, but I'm happy." she said, and he blushed, but gave her a hesitant smile. "If you don't know what to do, let me lead, okay?" she said, and he nodded. She lifted herself up, and lowered again, making them both moan as her walls slid against his shaft. She did it again, and again, the pleasure started to overtake the pain. She went faster and went harder, shoving herself down on his dick as he tilted his head back and moaned.

"Ah-!" M-Makoto!" she cried his name as she rode his dick, her breasts bouncing.

"Mmmm-! K-Komaru!" he cried back.

After a bit of this, she sighed and pulled out entirely, to which he stared at her in confusion yet again. She got off the bed, and pulled Makoto off as well. She turned around, and bent over, leaning on the bed as she spread her legs. He went wide-eyed as he stared at her, and she nodded with a smile. He gulped, and grabbed onto her ass, which was smooth and firm, and started to push his dick into her pussy, making her moaning start back up as he started thrusting into her.

"Ahhhh-!" Waves of pleasure rolled over her as he pushed his dick in and out of her, squeezing her ass hard as he did. Her breasts continued to bounce as he sped up his thrusts, getting faster and faster. His moaning joined hers as he pounded into her, feeling his dick throb inside her womb. He knew his climax was coming, but he didn't really want to pull out, and he figured she didn't want him to either, so he kept going, pushing harder.

"Komaru...I'm gonna...I'm gonna cum!" he said.

"M-me too! Let's cum together!" she exclaimed. He was going as fast as he could, his dick sliding in and out of her dripping pussy. He kept going until, finally, they both gasped and shuddered as they climaxed as one, his semen filling her insides as her cum shot onto his dick, mixing in the middle. Some of it dribbled onto the floor. It took a moment before Makoto pulled out of her once he had emptied himself, and they crawled onto the bed next to each other. Komaru's pussy kept dripping a little bit of their mixed cum.

"We...are never...doing that ever again…" Makoto said, and Komaru laughed. She turned to him and snuggled against him.

"I love you." she said.

"I love you, too." he said back as he kissed her forehead. They laid there for a while before Makoto told her to go back before their parents came home and found them. After giving him another kiss on the lips, she gathered up her clothes and walked back to her room on shaky legs. Without bothering to get dressed, Makoto walked to get some paper towels from the kitchen, cleaned up the cum, threw it away, and fell onto the bed, still nude. Back in their own rooms, the two siblings fell into a deep, peaceful sleep.