Disclaimer- I do not own the Vocaloids, unfortunately. -cries-

Author's Note- Hello, this is my very first Vocaloid fic, and I was inspired to write it after reading some other fics with the same general plot idea. Just my take on how the whole Rin getting Vocaloid Len should work out.

"He's yours now, Rin."

A nine year old girl stared with large, curious, turquoise eyes at the gigantic glass case before her. Inside was a young boy, probably around her age, who looked as if he was sleeping peacefully on white silk bedding, yet there was no rise or fall of the chest to indicate he was alive and breathing. It was a rather morbid sight, as if the container was a coffin, not a case. A heavy instruction booklet rested beside the boy, both safely protected by a number pad lock on the side of the case.

"What is he?" the girl held her bunny plushy close to her chest. The boy, whoever or whatever he was, looked an awful lot like her. At first glance, she could have sworn she was looking in a mirror. But there were some obvious differences: his face wasn't as round, but more angular, and his hair was a rather mussed-up darker blonde, tied up in a little, high ponytail.

"He is a Vocaloid," a man next to her marveled as he peered into the glass case, "His name is Len. Daddy took some of your pictures to the lab, and his scientists made him for you, even though it took six years. But don't worry, he's not a robot or anything. Len's body is human... well, mostly. He's got a heart, brain, liver, bones, muscle, and other stuff like that. I think he needs to eat, not sure about sleeping… or going to the bathroom… But anyways, he's got some extra stuff too that make him extra special."

"What kind of special stuff?" Rin stepped closer to her father and delicately grasped two of his fingers with all of hers.

"Well, for one, his brain is part computer, which makes him super smart. His muscles and bones are also genetically altered to be stronger than and superior to that of a regular human's, so he can protect and play with you when Daddy's not around. And, he's supposed to have an amazing voice, so he can sing you lullabies, like Mommy used to before she passed away. Quite astounding, actually… A human base enhanced through computers… a hybrid between the two most powerful forces in the world… the perfect fusion of technology and nature…"

Rin couldn't exactly understand what her father was saying, but continued to stare at the Vocaloid's face. Len, huh? "So… is he my brother?"

Mr. Kagamine blinked, then chuckled, "You could say that, yes. He's not related to you in any way, even though he's based off you. I guess he could be considered your adopted brother, then. Your mother always wanted you to have another sibling… Being left alone is an awful feeling, Rin…" his eyes held a far-off look.

"But you're not alone, Daddy," Rin pouted, "You have me! And I have you! And sometimes, Meiko and Kaito come over too!"

He smiled sadly, "Thank you, Rin. But you know Daddy has to work a lot, and can't be around all the time. Plus, Meiko and Kaito can't always come over, they have to go to school and stay with their families too. This is why I got you Len. But," he leaned down to her level and stared her straight in the eye, "Remember one thing Rin: you must never tell anyone that Len is a Vocaloid. If anyone asks, say he is your brother. Got it?"

Rin furrowed her brows, "Why not?"

"Because," he gently smoothed the puffy, white ribbon in her hair, "If anyone were to find out about Len, they may want to use him for bad things. Nobody knows that someone like him exists, or is capable of being created. Daddy had the scientists in his company make Len for you, and for Mommy, because she didn't want you to be alone. Now, let's go figure out how to activate him." He stepped over to the glass coffin, Rin in tow, and pressed the number pad lock on the side of the case. A beeping sound emanated as the lock flashed green. Rin watched her father gently let go of her hand and pop open the lid of the case, exposing the Vocaloid to open air.

"Let's see here," her father picked up the heavy book that lay beside Len. On it were the letters 'M-A-N-U-A-L', "Hmm… to activate, the user must donate a small sample of his or her blood to the Vocaloid. A drop or two should be sufficient to jump start the life-source generator. Begin by opening the Vocaloid's mouth. Next, deposit the sample and close its mouth. Allow a minute or two for the blood to engage the initial starting sequence. Finally, to "awaken" the Vocaloid, simply say the its name; note- the Vocaloid will accept and respond to only the designated owner's blood and voice. The designated owner cannot be changed, for his or her D.N.A. sample was integrated into the Vocaloid's brain during creation, so the Vocaloid will recognize only that owner's blood upon activation. Well… the instructions seem simple enough. Are you ready, Rin?"

Rin tugged at her white sundress and hid shyly behind her father's leg. She hadn't a clue what he just said.

"Don't be afraid," he smiled gently at her, "All you have to do is open Len's mouth, put some of your blood in, and then say his name. But we'll have to prick your finger to get the blood, and that might hurt a little." Rin jerked and stared wide eyed at the thought of pain, "It's okay, it's okay!" her father attempted to soothe the horrified girl, "Daddy will get you a band aid and kiss it after, okay? Then we can go get ice cream with Kaito and Meiko."

At the mention of the last event, Rin grinned and threw her arms up happily, "Ice cream, ice cream!"

Mr. Kagamine laughed, "Now hold still Rin…" He withdrew a pocket knife from his pants and gently took one of her tiny hands in his, "This may sting a little…" and quickly, but precisely, he nicked a small incision on her ring finger. Rin winced from the pain, and whimpered as her father gradually applied pressure, drawing out more blood. He then reached over to Len and opened his mouth, slightly surprised that his skin was so soft yet cold, and brought Rin's hand to hover over the opening. The blood, now swelled to a healthy size, clung lazily to Rin's finger before finally dripping into Len's mouth. Quickly, Rin's father closed Len's mouth again, and checked his watch.

"Now we wait one minute. Stay right here, Rin, Daddy will go get the rubbing alcohol and a band-aid for you, k?"

"K-Kay," Rin whimpered again, snuggling her bunny plushy closer with her other hand. Slowly, she walked closer to examine Len. His cheeks, which were an incredibly pale ivory, now turned a healthy, creamy peach, with a tiny bit of pink splayed across to indicate life and warmth. She could faintly feel his chest start to move up and down in an awkward rhythm, probably his first breaths. But why wasn't he awake? Oh yeah! Daddy said there was another thing they had to do. What was it? Say his name? Well, it wouldn't hurt to try…

Feeling more courageous, Rin sat on the floor beside the case. She reached out a hand to touch his face, surprised that it was actually warm and soft.

"Here goes nothing," she murmured.

"Len."

…

No response. Rin cocked her head to the side, "Did I do it wro-UWAH!" Rin yelped and fell backwards as Len's eyes suddenly fluttered open, revealing intense, vibrant cerulean irises. It was then that she noticed another difference. His eyes were narrower than hers, and held this intangible, mysterious quality to them, almost like an inherent sadness. Rin screamed again as he snapped upright, pupils dilating and adjusting to the light of the room. His ears perked. Her scream must have alerted him. Slowly, Len turned toward her, tilting his head curiously.

"Kagamine… Rin?"

He spoke! "H-How do you know my name?" Rin stuttered, slowly backing away from the newly awakened Vocaloid.

"Your identity is integrated in me. How could I not know my designated master? I am based off your image, after all," his eyes grew wide at her alarm, "Oh no, did I frighten you? I'm sorry! Please don't be afraid! I-"

The sound of hurried footsteps interrupted him as Rin's father came rushing into the room, clutching a bottle of rubbing alcohol, a cotton ball, and a band-aid with little oranges on it, "Rin! What's wrong? I heard you scream and…" he suddenly trailed off and stared wide-eyed at the newly activated Len, who was also observing him with curiosity, "R-Rin, you said his name?"

"I-I'm sorry!" Rin cried and hid behind her bunny, "I thought I was supposed to! Did I do something wrong?"

"No, no!" he shook his head vigorously, "You did great! Amazing… he actually works! I'll definitely have to give those scientists huge raises and paid vacations for this. Come on Rin, don't be shy, come and meet your new brother."

Mr. Kagamine smiled and reached into the case to help Len out, straightening his clothes which had wrinkled from lying in there for so long. Len wore a white sailor shirt, with a black collar, gold trimmings, and yellow tie. His shorts and leg and arm warmers were all black with gold trimming. And to finish the ensemble, Len wore a pair of clean, white sneakers. On the spot where Len had been lying was a cable.

"What's this for?" Mr. Kagamine inquired as he held up the mysterious wire.

"That would be my connector cable," Len surprised the older man with the sound of his voice, "You hook one end up to a computer, and the other to a small plug on my spine," Len raised his shirt a little to show an outlet on his lower back, "Then Miss Rin can download songs onto me, or whatever else information she wants to. I can also access the internet, hack into other programs, etc."

"I don't believe the latter part is necessary," Rin's father smiled, "What else can you do?"

"The manual has most of the information you need in it, but it's also programmed into my brain in case you'd rather ask me directly and not search through all those pages," Len grinned, "I'm capable of many things. Rudimentary functions such as cooking, self-defense, the Kagamine family information/history, and calculating have been programmed into me, in order to better help me serve Miss Rin. I'm also physically superior to other humans," Len trailed off and took a few steps back. Before the older man could inquire as to what he was doing, Len suddenly leapt and flipped clean over his head, before landing gracefully on the plush carpeting. The man's eyes widened. Incredible! This boy, who was no taller than your average nine year old, had managed to easily jump over a six foot tall man with only a few steps of running preparation.

"Wooow," Rin sighed, amazed, "That… was so cool!" she cheered and ran over to Len, with a bright grin on her face.

Len blinked with a curious face, seemingly entranced for a second, but then smiled back, "Thank you, Miss Rin. Anything that will make you happy." Rin blushed a little and covered her face with her bunny's ears.

"So what about your functions? Do you need to eat? Sleep? Use the bathroom?" Mr. Kagamine squatted on the floor in front of Len.

"Being that my body is still mostly human, I do need to eat in order to constantly refuel my cells," Len explained, "but I require a much higher amount of energy than regular people, so every bit of food is used up to maintain my functions. Therefore, I don't produce any waste. As for sleep, I can, but don't need to, since the energy I absorb from food allows me to stay awake 24/7; however, if I don't eat enough, I'll be deficient in fuel and thus just as prone to falling asleep as everyone else."

"Really? How much do you have to eat in a day?"

"About 15,000 calories."

Mr. Kagamine would have spit out his coffee had he been drinking any. 15,000?! Really?! That was almost eight times the amount of that of the average person! …Well, it did sort of make sense, since Len was an extraordinary being, who probably required quite a bit of energy to sustain, "Guess I'll have to go grocery shopping later," he grumbled, "Just how human are you? Do you feel emotions? Go through puberty? Suffer odd biological phenomena such as getting a sick, or having your voice crack?"

"As you should know," Len settled himself comfortably on the floor, "I was born synthetically from a D.N.A. sample of one of your scientists' sons, who passed away years ago. They cloned that D.N.A. to begin creating a human, but when I was still in my 'fetal' stage, they began altering me by synthesizing materials with my tissue. My bones, for instance, have some type of metal in them, that will prevent them from ever breaking and allow me to handle the stress and strain of manual labor much more efficiently and easier than your average human being. I have most of the same organs you do, like a brain, though it is half computer, lungs, and a heart. Some, like my spleen and bladder, were deemed unnecessary by the scientists and removed in order to make room for other things, like my life source generator. But I still feel regular emotions, though, in order to better connect with my surroundings. They left behind most of the organs responsible for hormone production; my reproductive organs, for example, are functional. The scientists said that I wouldn't be able to sympathize with or experience life as a regular boy if I didn't have that."

Mr. Kagamine began to cough profusely in order to interrupt his daughter from questioning what that meant. He also didn't really want to be hearing this from a nine year old, either, or at least a boy who looked nine.

"Well, that's enough questions for today," Mr. Kagamine stood dusted off his pants, "Aw, Rin, I forgot to bandage your finger. You got blood all over your bunny now."

"Eh?" Rin looked down, and sure enough, there were dark red splotches on her beloved stuffed animal's tummy. Tears started to well in her eyes, "Daddy, he's dirty! C-Can you clean him?"

"Of course I can," Mr. Kagamine gently took the bunny from his daughter, "Rin, why don't you take your new brother outside and get to know him? Tell him about the rules of the house and such, yeah? And while you guys go play, Daddy will clean Mr. Bunny here and then go grocery shopping to buy food for Len."

"Okay!" Rin beamed as she turned to Len and grabbed him by the arm, "Come on! We can go play on the hill."

Mr. Kagamine laughed and shook his head as he watched his daughter pull the poor boy a little too eagerly by the arm. He fumbled along, not yet used to walking, but could jump over a six foot man no problem. "Oh the wonders of modern technology," he sighed and headed toward the laundry room.

"So, you're like, part computer, huh?" Rin said as she started picking some red flowers.

"Yes. Well, mainly only part of my brain is. The other stuff inside of me doesn't function as a computer by itself, but goes with the one in my brain," Len replied, curiously watching Rin's every move.

They were laying on one of the hills beside the mansion. It was a rather isolated estate on the outskirts of town. The nearest people were a few miles away, and the town was a good few hours away worth of walking. But being alone had its perks, as Ren could run around freely on their acres of land without having to be suspicious of kidnappers, and with all the open land it was easy to spot if anyone was coming.

The estate was divided into three parts: the main complex, the recreational area, and the open land. The main complex was where the mansion was. It was a vast, highly modern building in terms of architectural design and décor, with way many more rooms than was necessary for one family of three. It had all of the state of art technology in terms of computers, media, and security, but Mr. Kagamine kept it relatively simple when it came to household luxuries like a dishwasher. They had them, but discouraged use of it because he didn't want Rin to grow up lazy and rely on buttons or just shout out her demands all her life, and expect them to magically appear before her. The recreational area was equipped with a formidable sized pool, half indoor and half outdoor, with waterfall, and a spa area, complete with pool house for lounging. There was also a basketball and tennis court, but was rarely used. The open land, in Rin's opinion, was the best. Vast stretches of fertile, green hills, with cherry blossom trees dotting the landscape here and there. Right now it was summer, and the cherry blossom trees, though they were not in bloom, were a light, playful green, and the grass was abloom with wild flowers, giving the impression that a rainbow carpet had draped itself across the land.

"You must know everything then," Rin raised one of the red flowers to her nose and inhaled the aroma, "Since you have a computer in your head."

"Not everything. Just whatever is programmed into me beforehand, and whatever I pick up along the way. My brain is still part human, so I can observe and learn like you, Miss Rin."

Rin frowned a little, "Don't call me that. Just call me Rin, okay? Daddy said you were my brother now, so it'd be weird if people heard you calling your sister "miss". Siblings don't do that."

"But it wouldn't be-"

"No buts!" Rin commanded, "I'm your master now! …I think, but I order you not to call me that!"

Len looked down, dejected, "Alright Mi-… Rin."

"That's better," Rin poked his cheek and giggled, then went back to picking the red flowers and arranging them in an intricate pattern.

"Mi-" Len started, but caught himself, "Err, Rin, might I ask what you are doing?"

Rin looked up from her weaving and grinned, "You'll see! Just wait a few more moments…"

Len leaned in closer to get a better look, but Rin hunched over her task, blocking it from view. "No peeking!"

Len frowned and slumped on the grass. Why couldn't she show him? Didn't she trust him?

"Finished!" Rin piped, snapping him from his thoughts. She beamed and proudly showed him her masterpiece: a crown meticulously woven from those bright red flowers she had picked earlier.

"It's beautiful," Len gasped, "What's it for?"

"It's for you, silly!"

"Me?"

"Yup! Now hold still," Rin scooted closer to the boy and gently placed it on his head, giggling as a petal fell from one of the flowers and landed on his nose, "You look so pretty, Len! Like a princess." Len blushed, not sure if he should feel insulted or grateful for that comment. Suddenly, Rin's eyes twinkled, an obvious indication that an idea had formulated in her mind. "Say, Len, would you like to play a game?"

"What kind of game?"

Rin stood and placed her hands on her hips, "Let's play pretend! I'll be the princess, and you can be my knight who saves me from the dragons and stuff!"

"But there aren't any dragons around, Miss Rin, how will I defeat them if-"

"Of course there aren't any, silly! And I told you to call me Rin, remember? Well, I guess for this game you could call me that. Or Lady Rin. Or even Princess Rin! Anyways, that's why it's called 'Pretend'. You pretend there's a dragon there, and then you pretend to vanquish it! Got it?"

Len frowned and tilted his head to one side curiously. How and why a person would want to find enjoyment out of imagining things that weren't there was beyond him, but he decided to play along anyways. "Alright," Len bowed on one knee, "You are my lady, and I am your servant."

Rin giggled giddily, "Yes, just like that!"

The two spent the rest of the afternoon chasing fairies, vanquishing dragons, and fighting wars. At first Len had stumbled along awkwardly, with no real idea of how to go about this "pretending" business, but after watching Rin pick up her skirt in a regal fashion and designate an elevated tree root as her "throne", Len started to get the hang of it. Rin was quite the demanding princess, asking Len to fetch her this, fight that, collect this, anything to test his physical fitness. Rin delighted in the amazing stunts his body was capable of. But Len didn't mind the exhaustive tasks his lady bestowed upon him. Seeing that sparkling smile on her face every time he returned "victorious" made an odd, contented emotion swell up within his chest. Was it pride? Happiness? He didn't really know, but all he knew was that it felt right, and he wanted to continue doing it.

Finally, at the end of the day, Rin decided to finish it off with a royal tea party. Len had run back into the house and grabbed some treats Rin's, or rather their, father had left on the counter for them. "Today's snack is brioche," he announced triumphantly as he offered the small piece of rich, buttery bread to his princess. Rin's eyes glittered as she fell back onto the grass with a laugh. She hadn't smiled this much in ages, and it felt really good to connect with someone more her age. Well, more or less.

"It's getting late, Lady Rin," Len propped his head up on one elbow and gazed curiously at his master. For some reason, there was always something about her appearance that intrigued him to no end. "The sun is starting to set. We should probably get back, it's probably dinner time."

"Hmm… I guess you're right," Rin mumbled. She sat up and smirked at Len. "Carry me back,"

Len blinked, but then smiled and bent down to offer his back to her, "As my Lady wishes."

Rin was mildly surprised that he didn't argue or whine about back aches like Daddy did, but leapt up giddily and wrapped her arms around his neck from behind.

"Now hold on tight," Len said as he carefully stood, hooking both of her legs on either side with each of his arms to ensure she was secured against him. Rin gasped at the ease with which he was carrying her, as if she weighed nothing but a feather to him. In reality, that's what it felt like for Len, also.

"Hey, Len," Rin rested her chin on his shoulder.

"Hmm?"

"Daddy said you had an amazing voice. Will you sing for me?"

"Sing?" Len tried to turn to look at her, "I don't have many songs in me right now, but what would you like to hear?"

"Anything," Rin yawned, "Something soft and smooth, like a lullaby."

"I know one. It's not really a lullaby, but without music the melody is actually really soothing. I think you'll like it. It's called Fortune Diver."

Rin closed her eyes as Len began singing. His voice was unlike anything she had heard before. It was light and airy, yet still had this smooth, echoing quality to it. By now the sun had already disappeared over the horizon, and stars were beginning to show up. Rin sighed and felt her body limp. The days events seemed to have really tired her out… not to mention Len's singing was so calming…

Before she knew it, Rin was already fast asleep, and snoring lightly on Len's shoulder.

Review? Please don't be too harsh, -fragile- Dx.