Author's note: This is my first ever fanfic, I hope it didnt turn out too bad~

This'll be a series of one-shots, each concentrating on a different pairing, about how they end up in each others' beds :3 But it all stays on a rated T-level xD I'm sure there are several fanfics like this, but I wanted to add my own version :)
Completed Pairings: twincest LenxRin, MikuxKaito, LukaxGakupo, MikuoxMiku
Planned Pairings: DellxHaku

I wrote this one under the heavy influence of Adolescence and the Kagamine version of magnet xD

Don't hold your breath for the next update though, I'm lazy~

A huge thanks to Sakagami Hina for proofreading my chapters :D

Disclaimer: I do not own the Vocaloids. I really, really wish I did, though.

Len & Rin

Hot. So very hot. Where does all this heat come from in the middle of the night? The blond youth lamented his misfortune, tossing and turning in his bed. The cool shower he took beforehand had quickly been rendered worthless.

If only I could open the window…First thing tomorrow, I'm bribing Kaito with ice-cream to put up the mosquito screen already! This thought gave him a tiny bit of hope for the following night, at least. Not only was this summer especially hot, but mosquitoes were everywhere and seemingly resistant to any kind of repellent. A screen was the best way to keep them out of the house.

But first, I need to get through this night somehow. Keep the window closed, and I'm cooked alive. Open the window, and I'm eaten alive. Sixteen is way too young to die! The boy took off his banana-print pyjama shirt, hoping to ease his discomfort. Haha, yeah right, not a chance.

After nearly an hour of turning about in his bed and extreme annoyance at the suffocating heat, a brilliant idea struck him. Rin has air conditioning in her room. A wide smile spread across his face.

How could I forget? It used to be our room, until just a few months ago…This last thought transformed the wide smile into a much smaller one.

As twins, Len and Rin were inseparable during their childhood. The two of them were the only ones existing in their world. That's not to say they didn't get along with the rest of the Vocaloids in their family, but they didn't share the same kind of close relationship like theirs with any of them. They played together, sang together, pranked the others together, drove their Road Roller together, ate their meals together (including snacks), slept together, in the first few years even bathed together. When someone bullied Len for being a crybaby, Rin stood up for him. When Rin was sick, Len took care of her all day and all night, not letting anyone else near his precious sister. There were no secrets between them, and they often finished each other's sentences. Like one soul in two bodies.

With the passage of years, though, adolescence broke them apart. Occasionally it felt awkward to be so close to one another. It was unnoticeable from the outside at first, but they felt a change in their bond near the end of middle school. Neither of them could put this feeling into words. When they entered high school, Rin started hanging out more with Miku, Luka and Gumi. Luckily for Len, quite soon after, Kaito and Gakupo recruited him to their visual kei band, VanaN'Ice, thus not letting him worry over it much.

It was Rin's suggestion to no longer share a room. Len didn't question her decision, and offered to move out, into the room straight across the hall. He wasn't too happy about it, and he didn't understand what he did to make her suddenly feel uncomfortable about living in the same room, but if that's what his dear sister wished for, then he'd fulfill her wishes to the best of his ability. The other Vocaloids were surprised at this abrupt change. By then, they too had noticed the alteration in the twins' behaviour. Blaming it on puberty, they didn't voice their concerns to them, and hoped it was just a phase that would pass soon.

His brilliant idea to sleep in Rin's room was overshadowed by uncertainty. How will Rin react, if she unexpectedly finds me in her bed in the morning? She wanted the separation in the first place…Sheesh, it's too hot in here! Surely she prefers her brother not burnt to a crisp. Although, for some obscure reason, lately she's been acting like it'd make no difference to her even if I were to drop dead all of a sudden. Well, if I'm destined to die anyways, I rather have my own twin kill me than something silly like the heat or mosquitoes. Following that logic, he dismissed any anxiety that remained.

Len climbed out of bed, and left his room that resembled an oven more than anything else at the time. He tip-toed across the hallway to her room and carefully opened the door, to make the least sound possible.

As Len stepped into Rin's room, he could already feel the cool breeze, thanks to the opened window and the running fan. The familiar scent of oranges lingered in the air. He looked around the room, taking in the sight of the objects he used to see on a daily basis: the pastel orange wardrobe with clothes falling out, the light orange-framed mirror covered with their pictures, the dark orange desk covered with a random assortment of papers and books, the trash bin containing orange peels. The room was only half-filled with Rin's belongings. The furniture wasn't rearranged; if Len wanted to, he could bring over his things at a moment's notice and put them back in place, like he'd never left.

It's almost as if she's waiting for me to return…Dream on, idiot. He shook his head, hoping to shake the childish idea out of his mind. Just because you love her unconditionally in a non-sibling way doesn't mean she reciprocates those feelings. She kicked you out in the first place, without an explanation.

The day after he moved out was when Len's emotions finally took shape in his mind. He realized that their bond, from his side at the very least, was more than what twins usually have. Len loved Rin, and would do anything for her. Her attempt at pushing him away only resulted in making him love her more. So in retrospect, moving out was the right decision to make, for the sake of protecting his beloved sister from himself.

Len's gaze reached the bed, and laid his eyes on a princess sleeping there. His cheeks took on a soft pink colour. Holy bananas, she's gorgeous! Rin's expression was peaceful, a faint smile on her lips. Her orange-print nightgown suited her form perfectly; she had already kicked off the blanket, allowing him to see her full figure. Her short, blonde hair fell elegantly on the orange-shaped pillows. It was reassuring that she was sleeping on the right side of the bed, leaving more than enough space on the left for Len to sleep comfortably without disturbing Rin.

For a few minutes, he just stood in the doorway and stared at her, completely enchanted by her surreal beauty. A wave of sleepiness washed over him, reminding Len of the reason he was here in the first place. I'm supposed to be sleeping, not staring at my sister like some creepy pervert! A pang of guilt stabbed at his heart for his behaviour, and he let out a deep sigh.

Very silently, he made his way to the bed and lied down, trying not to disturb her in the process. Much better, he thought to himself, enjoying the coolness of the room. He closed his eyes, attempting to fall asleep.

Suddenly, Rin started squirming; Len's eyes snapped open like a reflex to look over at her. Please don't wake up, please don't wake up! A second later, she turned over to face him, moving her arm to rest on his torso. Len started blushing madly. Damn, I forgot to put my shirt back on. The soft touch of Rin's skin on his body quickened the pace of his heart. Great, I can add heart-attack as a potential method of dying for the night.

The cool breeze seemed to magically disappear, once again Len felt suffocated by the heat. Maybe this wasn't such a good idea; I'm back to square one! The remorse was only in his words; his emotions were on cloud nine for being able to sleep in the same bed again, even if he didn't quite exactly have Rin's consent.

Though Rin didn't seem to mind her brother's presence. Shortly afterwards, she instinctively snuggled closer to him, using Len's chest as a pillow and hugging him tightly. His face took an even deeper shade of red, and his heart felt like it was about to explode.

The mind forgets but the body remembers, eh? We always slept like this...well, almost...Len gently placed his arm on her back, desperately hoping she wouldn't wake up to his touch. Perfect, just like in the good old days.

The sleeping Rin didn't find it perfect enough; she hooked one of her legs with Len's, pulling herself even closer to him. It'll be a miracle if I survive 'til morning like this! Due to this unexpected position, his body heated up even more than before; it was worse than back in his room, but there was no escape now without waking up his sister. Len fought the urge of letting his fantasy run wild, which wasn't an easy feat with the sensation of her warm breath on his body and the soft tickling of her hair.

"Len..." Rin mumbled softly in her sleep. He wasn't even sure if it was just his imagination or she really did call his name.

"Len..." she called out again. Rin really is calling my name in her sleep...can she tell I'm here? He didn't have much time to ponder on that, since she continued to whisper.

"Len..." she repeated his name for the third time, before continuing. "I..." she paused for a moment, then he could only hear an incoherent, mumbled word. "You..." she finally fell silent.

Oh great, I missed the most important word. Hate? Detest? Or something completely nonsensical like ate the last cookie before me? He was used to his sister's sleep-talking, he rarely woke up to hear it in the first place, and even when he did, it was just a string of random words. So this time, it really piqued his curiosity as to what she could've said, since it was actually semi-comprehensible.

"Len, I love you." Rin whispered, yet he could hear her quite clearly. That's it, I'm dead. I'm dying in euphoric joy. Len didn't want to believe his ears, so he pinched his cheek with his free hand to make sure he's awake. Maybe it's not even me. Len isn't such an uncommon name, is it?

He attempted denying what he heard, but he simply wasn't capable of it. This is too good to be true. Too, too good. Was pushing me away just an act from her? It became even harder for Len to keep a hold on his imagination. The girl he loved was in his arms, and she returned his feelings.

"I love you too, Rin." he said, almost inaudibly, on a sudden impulse. Even if she couldn't hear it in her dreams, he had to say it, because who knew when he'd have a chance again? Like a spell that released him, the cool breeze returned to the room, his complexion regained its original color, his heartbeat slowed down to normal again. Within moments, Len fell into slumber.

The orange curtains amplified the rays of the rising sun, shining brightly on the Kagamine twins sleeping tranquilly. The morning found them clinging to one another, their arms and legs completely entangled.

Len woke up first, and the first thing his eyes were blessed with seeing was Rin's angelic sleeping face, merely millimetres away from his own. Am I still dreaming? Or am I really holding her in my arms again after so long?

A second later, she awoke as well, her aquamarine eyes transfixed on the identical ones of her brother. They were mesmerized by each other's gaze. A minute that felt like an eternity passed by without a word, only the morning serenade of the birds outside the window could be heard.

"Wh-why are you in my bed?" Rin managed to stutter, shattering the silence between them. The entirely logical question made Len blush lightly. Definitely not dreaming now.

"I, uhm, aaahhh, y'see, well..." Len searched for the words to say. Damn, I didn't think of a good'll be too obvious if I make up a lie on the spot.

"Itwashotinmyroom, soIcameheretosleep, sorry!" he blurted out rapidly without a second thought, the blush on his face deepening, shutting his eyes to avoid seeing her reaction. Rin giggled at his embarrassment. Giggling is a good sign. If she were truly mad, I'd be experiencing pain already.

"It's okay, I didn't mind. You were c-comfortable." It was her turn to blush. Safe, barely. Relieved, Len opened his eyes and smiled at his twin, receiving one from her as well. He couldn't help but rest his eyes on her cute, pink lips. I wonder what they taste like...probably oranges.

"Why are we entangled like this, where's your shirt, did I sleep-talk and say anything weird?" The string of questions bounced off her lips; it took a few moments for Len to realize that he was supposed to answer. Snapping out of his thoughts, his face could've passed for a tomato. I need to get farther away from her, before I do anything I'll regret later...

He started pulling away from Rin, but she held onto him tightly. "I asked you why, didn't tell you to stop..." she snapped at him. Len laughed, recalling what he heard last night, overjoyed to have it subtly confirmed. So the events of the night weren't just a dream either.

"I swear we weren't like this when I fell asleep..." he started replying. "And I left my shirt in my room because it was hot in there and I thought taking it off would help. It accidentally stayed there when I came here..." he paused for a moment. That sounds really lame, I know, but please believe me! "As for sleep-talking, what counts as weird?" he asked carefully. Letting her know she basically confessed to me in her sleep seems like a worse idea than lying.

"So I did say something, didn't I?" she returned the question with another one. Argh, she's cornering me! Len started disliking the direction this conversation was headed towards.

"Yes." he replied curtly. A short answer is the safest choice.

"What?" she continued with her questioning. Why so persistent? Is it possible that she knows very well what she said?

"What what?" he returned the question. Acting dumb is better than telling the truth.

"What did I say, idiot?" He could tell she was getting impatient; that's when she starts throwing around the friendly insults. She's much less angelic and much more devilish when she's awake...Len was afraid to answer.

"I-I don't re-remember." The stuttering didn't make his little white lie very convincing. Smooth, Len, very smooth indeed.

"Really?" Rin knew him too well for his own good; not even a small lie can pass by her unnoticed. He could feel the pressure on him escalating. This isn't gonna end well...

"Uh, no, I lied..." he stated. Now I really am a dead man. Rin didn't take kindly to being lied to.

"Oh, you don't say?" Rin abruptly interrupted. The girl's voice was dripping with sarcasm. Wow, no abuse? Len considered himself lucky for getting off the hook so easily.

"So what did I say?" she repeated her question. Len remained silent, furrowing his brows deep in thought. How am I supposed to answer that? Ohh what the heck, what have I got to lose? It's now or never! He stopped caring about possibly regretting his decision later.

"I love you!" he said out loud. Before Rin had a chance to say a word, he pressed his lips onto hers, hugging her in a tight embrace. Mmm, her lips really do taste like oranges. Len was glad she didn't pull away; quite the opposite, actually. She opened her mouth, letting their tongues explore each other's mouths. Holy bananas, I'm kissing my sister, and she's kissing me back! I didn't fall asleep again, did I? Their passionate first kiss lasted until they were both out of breath.

"I love you, Rin." Len repeated, in between gasps for air. "More than a brother should." he added, his voice slightly shaking. As if that kiss wasn't proof enough...

"I love you, too, Len. More than a sister should." Rin mirrored his words. If that's so, why did she distance herself in the first place? She pulled him closer for another passionate kiss before he could say anything. They only broke apart again when they needed to breathe.

"We're sharing a bed and room again, right?" Len asked, gently stroking her cheek. It doesn't matter why she kicked me out as long as I can be with her again.

"Do you even need to ask?" Rin retorted, before leaning in for another kiss.

I'll take that as a yes.