Kagamine Len isn't exactly sure when he started seeing his sister and singing partner in that way.

Maybe it was during their fifteenth birthday party, when Teto had set off the fireworks and she had squealed and cheered, her beautiful eyes shining in excitement. She had jumped around and talked about just how beautiful they were, and Len had agreed. But instead of marvelling at the fireworks, he had kept his eyes trained on his sister, because she was never this exuberant. Maybe it was when she had rolled down the grassy hill into the creek below, and had resurfaced dripping wet and laughing, a tendril of pondweed clinging to her forehead.

He knew for sure when the next day, when they had woken up, Rin had grabbed his hand and he had felt butterflies collecting in his stomach. She had said: "Look! If you look really hard, you can still see where the fireworks are!" and he had nodded and agreed and stared at her, a smile on his face.

Honestly, since when was his sister this dim?

But then again, how on Earth did you tell your sister that you were hopelessly in love with them. He had millions of UTAUloids dedicated to loving him, several absolutely gorgeous female friends, and he had fallen for his sister.

The press would have a field day if they ever happened to find out. And then, just like that, he'd be taken out of the singing business. No one wanted a pair of incestuous twins. And Rin- what would Rin say when she found out that she had been robbed of her favourite activity in the world because her brother was a sick pervert? She didn't even let it go when he stole one of her pencils!

She'd look at him, bewildered, then run away and never return to his side.

Stop it, he had tried to convince himself, you don't love her. She's your sister. You're just being weird.

But when he thought about it, there had to be a reason why he always let her lead. There had to be a reason why he was always so protective of her, angrily fending off bitchy UTAUs when they called her a flat-chest. She was proud, no doubt. In almost every song that they were in, either he died, or both of them died, or something happened to him. Yet he never complained, just went along with it and sung with his sister.

Honestly, how did you confess to your sister that you felt your heart flutter when she was pretending to kill you for a music video?

He could've fallen in love with Miku. She was bright and exuberant, and would've made a great girlfriend. Gumi was energetic and boyish. Luka was mature and helpful. Meiko was great for giving advice, not to mention a daredevil. Hell, even Kaito had his reasons for Len to be attracted to him. He literally could've fallen in love with one of the billions of UTAUs. It wouldn't've mattered if they hated him. He could've fallen in love with a Pitchloid for Chrissakes-

But nooo. He falls in love with his sister. God, it's like SPICE! all over again, except this time, he doesn't get the girl that he wants the most at the end. And he can't do anything about it this time, because honestly, he's not as brave as he thinks.

So Len sits at the sidelines and tries to ignore the falling feeling in the pit of his stomach when Rin sings a love song with Miku or Kaito and hopes that one day she'll start seeing him in that way as well.

Unlike Kagamine Len, Hagane Len can pinpoint the exact moment when he started falling in love with his sister, the fearsome and bitter Hagane Rin. And no, it wasn't immediate heed-over-heels puppy love. It had started as a mere warmth that had settled in the pit of his stomach, and had progressed to infatuation in less than a week.

It had all started at midnight, in the Hagane base. The massive black building was split into two, one side for the M-Types, and the other for the H-Types. Hagane Miku had been upstairs, belting out the lyrics to some English screamer song that she had learnt recently. Meta Luka was reading a overly-depressing psychology text about death to herself, smiling when something happened.

Len and his sister had been sitting on opposite end of the couch, watching Sinister. Neither one of them had suggested it- it had been in the DVD player when they had switched it on. Their faces were blank and expressionless, and they whenever something happened in the movie, one of them would silently yawn or cross their legs. It took nothing short of the upcoming apocalypse to faze them, and they were somewhat proud of this.

For Len, the movie had gotten increasingly boring by the minute, and so he had turned around and looked for something else to stare at. His sister kept her eyes trained on the screen, half-lidded blue orbs dilating every once and again. Unoticeable to the average person. He had started staring at his sister, and that was when it had happened.

They had never been close at all. They had grown up together, and sung together for all their lives, but they still treated each other like business acquaintances. They didn't confide in each other, didn't argue, didn't talk. Just sang together, and then went back to their lives. He had never even seen her smile. And now here she was, eyes widening and small gasps coming out of her mouth, and smiling when someone actually died. The ancient TV cast a soft, ebbing blue light onto her face which illuminated the facial expressions that he had never seen before.

Infatuation.

But even though Hagane Len was never one to step down when he wanted something, he said nothing. It was so wrong. Not because they were siblings. That was society's problem, and society could go fuck itself. It wasn't like he had ever been popular anyways, always being confused with Magane Len, so he wouldn't have lost anything.

No, it was wrong because they weren't supposed to fall in love. Not only with each other, but with anyone. They were the Hagane twins, cold and spiteful, heartless and dull, and out of all of the Vocaloids which could've fit into that category, they were the most alienated to the weird, painful emotion named 'love'. And his sister- his sister wouldn't hate him for loving her, he was sure of that.

No, she would simply stare at him with those glassy blue eyes, then walk away and act as if he had never confessed.

He knows that that would hurt more than anything else in the world, and he's a coward in a way, not wanting to risk the pain, so he merely watches his sister and files the snapshots of her face into his cabinet for when he might need them at night.

Magane Len, the last Len, seems to be much less of a coward than his H-Type counterpart.

He didn't start falling for his sister at a specific time, he doesn't think, and the feelings didn't slowly build up from sibling love over time. No, none of those unnecessary complications.

Magane Len is positive that he was simpy born to love his sister. He loved her unconditionally since he could properly identify love, and had no problems with openly displaying it. He sent her chocolates and roses on Valentine's day, hugged her, kissed her, comforted her when she needed it. The only problem was that half the time, she thought he was just doing it as a joke.

He couldn't blame her for that. They were more than siblings, they were partners in crime. They did everything together. They even refused to sing alone or with another Vocaloid. And they knew everything about one another, which was why he hadn't held himself back, because he had already known that she felt the same way.

If he had ever discussed this with another Vocaloid, they would probably assume that he was being ridiculous and forceful and glare at him. He and his sister- they were together now, as a couple, and many a Vocaloid had assumed that he had beaten her into submission until he had convinced her that she loved him, or something like that.

Nah. Not even close.

There had been no need for confessions or anything like that. Their relationship had progressed without either of them saying a word about it. They had started off as mere friends. Within two weeks, Magane Rin would wake in the middle of the night to find her brother in her bed. They would hug each other at random intervals, hold one another when if they were depressed, and kiss each other as a sort of involuntary reflex whenever one of them was happy.

It had taken them a while to identify this as romantic attraction, however.

And when they had both finally consciously realised that they were in love with each other, there was no denial or self-loathing. No, none of those unnecessary complications. They just accepted it and went on with living their lives together.

They had been made to be together, after all.

Okurine Luka watches Hagane Len who is sitting with the other H-Types by the window seat oat the cafe. She reaches into the pocket of her jacket, pulling out a hundred dollar bill and slaps it onto the table. Kagura Gakupo eyes it greedily before slowly reaching into the pocket of his jeans and drawing out several twenty dollar notes.

"Yo, Kagura." drawls Luka, "if you can get emo screamer over there laid, I'll pay you a hundred bucks. If I get his sister laid before, you pay me."

"Sure, whatever."

At the table in front of them, Hagane Rin turns around and Hagane Len quickly looks away from his sister. Oh god, is he blushing?!

"You know," muses Isamine Kaito, sipping from his milkshake, "You might just run into a few problems with that..."

Both Gakupo and Luka turn to stare at him questioningly and Sakerune Meiko elbows him in the stomach. "Shhhh!" she whispers when they turn away, "you're gonna make this no fun to watch!"

"Speaking of incestuous awkwardness." says M-Type Miku, plopping into the seat next to Kaito, "guess which Chinese Vocaloid was finally deflowered last night?"

Meiko and Kaito stare at her for a few seconds before gasping. "No!" exclaims Kaito, "Really? He did that?Longya-"

Meiko holds up a hand to shush him. "Hold on, Kaito. You sure your sources are accurate?"

Miku smirks. "Heard from Mo Qingxian herself."

Meiko's eyes nearly bulge out of her head and Kaito emits a surprisingly feminine fangirl-like squeal and a babble of fangirlish nonsense. Gakupo rolls his eyes at him and Luka frowns and says: "You sure you're not gay? Or at least a girl?"

"Excuse you."

Hagane Len has finally noticed them and there is hatred etched into his face when he turns to them. Miku flips him the bird and elbows Kaito in the stomach so hard that he makes a retching noise and falls onto the table. He chokes melodramatically. "You've killed meeeee... Oh, it burns...the burn... I will never be able to molest Kagashota again... oh the divine retribution... the pain."

Luka snorts and Meiko falls out of her chair giggling.