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It had been three months since the synthister attack on Akihabara. Nanashi’s sister, Nana had finally decided to move out of MOGRA‘s backroom and in with him in his new apartment. Their relationship was better than ever, and now he was watching the new Striprism+. All was right with the world.
The girls were right in the middle of a transformation scene when the front door swung open. In walked Nana, wearing nothing but a school swimsuit. She looked like an otaku’s wet dream. “What’s up, brodeo?” She glanced over at the tv screen and looked at him, shocked and hurt. “Are you watching the new Striprism+ without me!?!? How could you, brotrayer!?”
Nanashi panicked as he realized his mistake. She’d never forgive him if he didn’t fix this. “I’m sorry! I didn’t mean to… wait…” he said noticing her skin looked much darker than normal. “Were you tanning?”
“Don’t change the subject. I’m gonna go get changed and when I come back you’re starting it over so we can watch together!”
He hung his head in immediate defeat but refused to let the previous subject go. “Fine. But seriously, since when do you tan??”
Nana looked a bit embarrassed. “Well… my friends said it might be a good thing if I went outside more and got used to the sun. So I’ve been working on my tan the past few days. Just because you’re cursed to look pasty white forever doesn’t mean I should be.”
Nanashi looked hurt. “It’s not like I can help it, you know. I’ll actually die if I try to get a tan.”
She rolled her eyes and walked away towards her room. “Whatever, just get ready to start the episode over and be lucky I’m not making you buy me a new figure to make up for it.”
Nanashi quickly shut his mouth, taking her threat very seriously. As she walked away he pulled out the remote and paused the episode. While he was waiting, he realized that he should probably get started on dinner soon as well. He walked over to his sister’s bedroom, knocked twice and let himself in. “Hey, Nana what do you want for din-“ he was stopped in his tracks by what he saw. Nana was bent over, her back to the door and her swimsuit lying in a pool around her ankle as she was pulling her other foot out of it.
Upon seeing her brother, she quickly stood up and covered herself. She then reached for the nearest heavy object and threw it at him. “Don’t you know how to knock, brovert!?”
He stammered out a quick “But I did knock, before turning and running to avoid being struck by an anime statue. In no time, he made it down the hall and heard his sister’s bedroom door slam shut behind him. He decided they should just eat ramen that night.
Nana came back out, still slightly red in the face but saying nothing about what happened. Nanashi handed her a cup of instant noodles and they sat in silence to watch the new episode together. Or at least attempted to.
Nanashi could barely pay attention to what was happening on screen. He just couldn’t stop thinking about what had happened. He wanted to say something to break the tension. He looked over at Nana, who was beet red, but still clearly enthralled by the show, and he thought better of it and chose to keep his mouth shut.
That night was brutal for him. As he lied in bed staring up at the ceiling the scene played out in his head again. The image of her perky ass flashed before him. Her tan body almost glowing in her bedroom light. Thinking about it now he could perfectly recall the curves of her body as she covered herself in embarrassment, almost looking like a girl in a harem anime. He felt a stirring in his loins and slowly reached his hand into the waistband of his pajama bottoms. When he realized what he was doing, however, he pulled his hand back and shook his head. “What the fuck am I doing?” He thought to himself. “I must be fucking sick in the head. That’s my sister!” This final thought caused his erection to settle down quickly, and with that he decided it was time for bed. He turned to his side and shut his eyes, but before he could fall asleep, one final thought crossed his mind. “She didn’t have any tan lines…”
The next morning, Nana must have still been embarrassed because she could hardly look him in the eyes. Which was fine by him because he would’ve had a hard time doing it himself. He attempted to make small talk with her. “I was thinking about heading to Main Street today. I’m gonna see if they have the new set of Striprism figures at Animate yet. Do you want to go with me?”
Against all odds, Nana’s face somehow managed to turn an even brighter shade of red. “No I think I’ll pass on that. You should ask Touko to go with you.”
He tried unsuccessfully to hide his disappointment. “Right… well I guess I’ll head out after breakfast then. Do you want me to pick you up anything? A new shirt or a figure maybe?”
Nana furiously shook her head and turned towards the door. “No thanks I’m gonna go get breakfast with my friends. Later, bro!!”
She spoke so quickly and was out the door so fast that he hardly had time to even register what she had said. His head sunk low as he realized she must’ve been really upset with him. He began speaking to himself. “God I’m such an idiot. She was really embarrassed and there I was fantasizing about her like a fucking creep. What’s wrong with me??” He decided it’d be best if he properly apologized to her when he got the chance.
Nanashi arrived home later that afternoon, new figures in hand. He made sure to get one for Nana as well. He knew she’d probably want one and he saw a new Chiyodan statue in the store. Speaking of her, he saw her shoes in the doorway and knew she must’ve been home already. It was now or never, so he decided he would go and apologize.
Outside of her door again, Nanashi was about to enter when he quickly realized what a mistake that’d be. He got ready to knock on the door when he heard some soft whimpering on the other side. It sounded like she might be crying. He knocked a few times. “Nana?” He called out. “Are you in there? Are you… okay?”
A startled voice came from the other side of the door. “J-just a minute!!” She cried out as he heard her shuffling around inside. After a few seconds she spoke again. “Okay, you can come in…”
He stepped inside and noticed a few used tissues sitting on her bedside table. She really was crying. She must’ve been more embarrassed than he thought. “Oh, Nana… can I sit down?” She nodded silently and he sat on the foot of her bed next to her. “Nana… I want to talk to you about what happened yesterday…” Hearing this, her face immediately turned bright red again and he continued. “I know… but listen. I want you to know I’m sorry. I didn’t mean to walk in on you like that. And I shouldn’t have barged in at all. But you know… you don’t really need to be so embarrassed. It’s not the first time I’ve seen you like that. After all we even still take baths together sometimes!” The look on her face told him what he had already been thinking. This situation was completely different from any time they took a bath together. He’d never ogled her body in the bath before. It’d always felt innocent and just like a normal thing between a brother and sister. But this… he continued. “Right… you’re right… this isn’t the same. And I’m sorry. I know you’re really embarrassed about me seeing you. Believe me, I’m a little embarrassed too. And I’m really sorry… I hope you can forgive me. And if it’s okay with you we can just move on and pretend it never happened. You won’t have to be embarrassed anymore because neither of us will even be thinking about it!” As he said the words, he knew in the back of his mind that it wasn’t true. He didn’t think he’d ever stop thinking about it. “I’m so sorry, Nana… I promised you that I’d take care of you and that we’d always be together. I didn’t mean to hurt you or embarrass you… I really hope you can forgive m-“ he was cut off by his sister suddenly leaning in and kissing him on the lips. She wrapped her arms around his neck and pulled him into a deeper kiss before pulling away and panting. He looked at her in shock. “N-Nana!” He didn’t know what else to say.
She turned away again, not willing to look him in the eyes as she spoke. “I wasn’t embarrassed because you saw me naked… I was embarrassed because of the way I reacted to it. Not at first. But afterwards. When we were watching Striprism I kept thinking about it and wondering what you thought of… what you saw. And that night, I couldn’t stop thinking about it more and… fantasizing about what could’ve happened… And… even just now before you came in here I was…..” her entire face was now a deep crimson shade and she couldn’t finish her thought.
Nanashi thought about the whimpers and the tissues and suddenly put two and two together. “O-oh!!” He then thought about it some more. “Wait… so you want to…” the realization hit him like a ton of bricks. “Nana, we can’t!!!”
She glared at him defensively. “Why not!? It’s not like we’re in America! It’s not uncommon for people to marry their own cousins here, you know!!”
“Nana, that’s cousins. Not siblings! And even that’s still pretty weird!”
She fired back with a quick retort. “And what about Rin and Shizuku!! They’re sisters but they still have that kind of close relationship!!” She’d clearly given this some thought.
Nanashi sighed and rubbed his eyes in exasperation. “That’s different… they’re Nighteaters, Nana. Just because it’s normal for them doesn’t mean it’s okay for humans.”
She refused to give up. “So what? You’re a Nighteater too, you know…”
His head peeled up at this sudden realization. Suddenly he was struck with all the motivation he needed to do what he’d been wanting to do the whole time. Without another word? He pulled his sister in for another kiss and they were suddenly locked in deep fervid embrace. They’d picked up insane momentum and we’re going from zero to sixty in no time flat. Within second, Nanashi was removing his sister’s parka and lifting her shirt over her head. Her cute, heart-print training bra was now in full view. Then, just as quickly, he pulled her skirt down around her ankles, revealing her matching set of pink heart-print panties. She was so cute he could hardly contain himself. His tongue was swirling around inside her mouth as his hand reached up and slid underneath her bra. His fingers swirled around and gently teased and played with her nipples. He softly caressed her barely budding breasts, and when he pinched her nipple between his fingers she shuddered in delight.
Meeting no resistance, he pulled her training bra off over her head, now revealing her cute little a-cup breasts. She looked embarrassed to be so exposed to him but her embarrassed expression quickly changed to one of pleasure when he leaned forward and took one of her small pink nipples into his mouth. He circled his tongue around her nipple and flicked it back and forth, causing her to lightly cry out with pleasure. He gently bit down on it and her soft whimper turned into a much louder moan. As he was doing this, his hand was slowly reaching down toward the waistband of her panties. Just as he was about to slide it inside, she grabbed his wrist and stopped him.
“Wait!” She said, causing him to pull away.
“Are you okay? Do you want me to stop?” He asked, switching over to big brother mode.
She turned away again. “N-no… it’s just that… well this is my first time so…” she looked at him again, her face now pink both from embarrassment and arousal. “Be gentle…?”
He smiled at her and gave her a quick kiss on the lips. “Of course.” He leaned down again and began kissing and licking her neck, knowing full well that it’d leave a hickey. He didn’t care. He wanted to leave his mark on her, even if nobody could know it was his.
As he nibbled on her neck, he again reached down towards her panties. This time, meeting no resistance from her at all, he slid his hand inside and noticed that she was already very wet. He traced a finger around her wet hole and gently slid one inside. Careful not to use more than one, and not to slide it in too deep, he used his finger to tease her. Slowly sliding it in and out and tickling the walls of her wet cunt. She shivered and let out several small moans as a jolt of electricity was sent all throughout her body.
After teasing her a bit more, he pulled his hand away and reached for the waistband of her panties, ready to slide them down. She covered her eyes, not wanting to see his face when she was completely exposed to him. After no more hesitation, he quickly slid her panties down around her ankles and pulled them off of her. He looked down at her small pussy. It was untouched. She’d likely never been penetrated by anything at all, even while masturbating. She was just barely staring to develop some peach fuzz around it. Other than that, it was totally bare. He leaned in closer to get a better look. She still refused to uncover her face, but she turned noticeably brighter red when she felt his hot breath against her bare flesh. Upon closer inspection, her lips were a pale shade of pink and she was very clearly dripping wet. The slight scent was enough to drive him crazy. He couldn’t hold back any longer and he leaned in and licked her all around her sweet pussy. The sudden sensation cause her legs to lock tightly around his head, and she pulled her hands away from her own face only to use them to pull his head even closer to her, clearly not wanting him to stop.
He took this as an invitation and began feverishly licking away at his sister’s cunt. He was still inexperienced, but was doing a more than serviceable job. He inserted his tongue in an out as if he was fucking her with it. The taste was indescribable, but incredible. Even more than that though, he loved her light moans as he did it. Every now and then he would graze her clit, causing her to scream out in pleasure. It wasn’t long before he figured out where the spot was that cause her to do this and began to flick his tongue across it and suck on it for her. The sensation was too much for her and she screamed out as she clutched his head even tighter and squirted into his mouth.
She released her grip on him, panting from exhaustion and ecstasy. He pulled his head away and showed with a grin that his face was dripping with her fluids. Not wanting to wait anymore he tore his own clothes off. First his shirt, and then his pants. His boxers were clearly tented out. He pulled them down, revealing his fully erect penis to her.
Her mouth hung wide open, and her face bright red. She was kind of embarrassed to see her brother like this, but was clearly drooling at the site. He brought himself closer to her, his erection now grazing against her stomach. “Are you ready?” He asked softly. She simply nodded her head. He positioned himself so that his dick was just outside the entrance to her now sopping wet cunt. “It’s going to hurt quite a bit at first” he warned. She simply nodded again, indicating that she was more than ready.
With that he traced the head of his dick around her sweet lips and slowly inserted just the tip of it inside her. The new sensation cause her to shudder with anticipation. She was almost not entirely prepared for how much it would hurt as he slowly began to slide more of himself inside her. It was a very tight fit and she could feel herself being slowly stretched out. Against her own embarrassment, she looked down saw that he was only about halfway in. She gritted her teeth and readied herself for the rest of it.
“Ready?” He asked again. When she nodded in confirmation, he quickly slid the rest of himself inside of her. There was a small audible tearing sound and a light trickle of blood spilled out. It hurt like hell for a second but that feeling was immediately replaced by a feeling of pure bliss. Now fully inside her, he began thrusting back and forth. First slowly, but quickly picking up speed. She’d masturbated before, but had never in her life felt a sensation quite like this.
Grabbing her by the wrists, he pulled her closer to himself so he could thrust inside her even harder. By this point he was fucking her silly. Going full speed and pounding her cunt, she was letting out screams of pleasure so loud he was glad they didn’t have many neighbors. After a few more minutes, Nana cried out as her pussy began to squirt again. And shortly after, Nanashi let out a few grunts as he unleashed a hot load inside her.
Pulling out of his sister, Nanashi let go of her wrists, allowing her to fall back into the bed. She was panting and moaning, clearly exhausted by her first time. With that, Nanashi threw himself onto the bed beside her, realizing just how exhausted he was as well. The siblings lied on their backs in silence for a bit before Nanashi turned to his sister. “So… how was your first time?”
Nana looked him in the eye and then quickly turned away, embarrassed. She stayed that way for a second before answering him. “It was… incredible…”
He smiled at her, then thought of something. “Have you had your period yet?”
She looked at him a bit confused and embarrassed by the sudden question. “N-no… not yet…”
“Good” he thought. “At least that means I probably don’t have to worry about her getting pregnant.” He then spoke aloud. “If we’re going to do that again, I’m going to have to get some condoms just to be safe.”
She looked a little surprised. “You want to do that again…?”
It was his turn to look embarrassed as he realized what he’d said. “W-Well I mean… if you want to… it’s not like I expect it to happen…”
Nana smiled and leaned in for another quick kiss. “Definitely.”
He smiled back and threw his head back onto the pillow. He turned away from her a bit before saying “I love you, Nana…”
Without missing a beat she rolled towards him and wrapped her arms around him. She gave him a wink as she said “I love you too, brother.”