"Akihiko-kun."

A little boy looked up from his action figures to see his mother holding her stomach. His father near her. Though he was young, he was precocious and already knew many things about the world. To him, it was pretty obvious… but pretty curious. His eyes sparkle as he stood up and rubbed her tummy, placing an ear over it. Eyes brighten up even more as he heard something. A smile broke through his cold appearance as he squeaked, "I hear something!"

The parents exchanged glances, amused by their normally silent boy's outburst. They had expected him to find out immediately—the kid had an IQ of 145 despite being only seven. But they didn't expect him to do what he would normally call pointless and stupid.

The mother smiles, "You're going to be a big brother, Akihiko-kun."

The father nodded happily, "Protect her as an Onii-chan please."

Akihiko once again smiled widely as he heard the pronoun. He was going to be a big brother!

…

Beep. Beep. Beep.

Kayaba Akihiko's eyes stayed transfixed on to the fragile body of his little sister. Her dark chocolate hair spanned across the sick bed, calling attention to her much-too-pale ivory skin. Her tiny body resembled a porcelain doll—one touch could break her. Well, technically not… but his eyes spoke of the worst.

She was sick. Delicate. Fragile…

She was going to die.

Going to die.

Die…

Just a few minutes ago, she had been laughing cheerfully and brightening the world with her smile. Though smart like him, Kayaba Haruko was not a cold, anti-social recluse. No. She was like spring—bringing light and happiness to the world with her mere presence. She warmed his heart with her bubbly mirth. She supported him with an extra dose of character strength while others misunderstood him. Heck, she even took up his hobby of computer programming, joining him in the world of virtual reality and cyber tech.

And she was only four years old!

But then, she fell. He could remember her clutching her chest, feebly trying to breathe. He could remember that moment where he first realized that she had gotten paler, that she showed signs of pain and fatigue. And he could remember frantically following her into the ambulance and later to the ER.

It was scary. Finding out that she had an incurable disease. An incurable disease from birth.

And it was maddening to find out that his parents knew. That her health was the reason why they seemed so stressed and tensed nowadays. That her health was the reason why they seemed to always blow up whenever she was around.

And it was downright frustrating to find out that she knew. That even she knew yet kept on smiling and cheering others up when it was her who was hurt the most. That she knew about her condition and the reason behind the unfair treatment that their parents gave her. That she didn't even bother to tell him. And that he was the only one who lived in ignorance.

He watched helplessly as his sister laid on the hospital bed—never before had she seemed so weak and fragile.

…

"Nii-chan, Onii-chan!" Small hands tugged his sleeve and he sleepily woke up to see adorable violet eyes. They were pure and filled with emotion. He smiled and patted her soft hair with his big rugged hands.

"Sorry. Did I fall asleep, Haru?"

She pouted cutely, "You did! Mou, if you're tired, then just stay home! You don't have to visit."

"But I want to. To see your pretty face and genius."

At that, she seemed to lighten even more and ran back to her bed, taking out her high-tech laptop. After a dozen taps across the keyboard, she turned it around, showing him the breath-taking scene of a castle floating in the sky. The metallic structure that showed great knowledge of architectural design and computer programming. Its intricate details and amazing silver brilliance, standing out of the midnight blues and purples. How the clouds seem to break apart from its brilliance and extend their wispy hands towards it…

"It's like Laputa, right?!"

Laputa. The Castle in the Sky. It was the first movie that they watched together. And even that was beautiful. He remembered when they were cleaning out the attic of their house. Haruko wasn't sick yet at that time. And then they found an ancient DVD (no one used those anymore) and played it on the old computer they found. It was an amazing animation that touched both of their hearts. A movie that showed the good and unique of the human race and how they could all help each other to do the impossible.

And most importantly, the castle in the sky. That was when he was first fascinated by how amazing castles looked when in the sky. Their majestic otherworldliness.

He smiled and nodded as eyes twinkled and glued themselves to the screen, "Just like Laputa… But since when did you start playing games, Haru?"

The girl grinned, "I met this boy who called himself Kirito! He saw me with the laptop and taught me about this game. He's a really nice guy!"

"…Kirito?"

"Yup!" And a few more taps and she pulled up a hospital archive, showing him a picture and information, "I hacked into the hospital's net. Here!"

He glanced to see a pretty boy, mentally sighing in relief. Seven was too young an age to be falling in love. Good thing that this Kirito guy wasn't her type. He rubbed her head again, proud of her growing hacking skills,

"Good job. Even I couldn't hack into this place's cyber security at your age."

She giggled with happiness as she heard the tint of pride. "So how's Nii-chan's project?"

He grinned, "Finished! Now this Nii-chan can play with you more until the next one comes up!"

…

AI. Artificial Intelligence. It was something that even today's scientists and programmers still couldn't make. Even when they found the cure to cancer and other once-incurable diseases, created virtual reality games, nerve gear, hovercrafts, and other stuff…

They still couldn't figure out a way to add a soul to the characters that they programmed. A way for them to think for themselves and become more human.

Yet now that he thought about it. It only made sense that the girl with a still-incurable disease would make the first AI.

"Ne, Yoru~ This is Nii-chan!"

The midnight blue nekomata glanced up and mewed cooly. Dark indigo eyes examined him warily while two tails flickered. It laid on his little sister's stomach yet tensed as he moved closer, as if it was her bodyguard or guardian and he was an attacker. The girl gently pet the cat,

"Yoru. He's Kayaba Akihiko. My older brother. He's… a nice guy."

And at that, it licked her hand in understanding and relaxed. It still kept an eye out for him though. Akihiko sat down on a fluffy chair next to the bed and curiously reached out for the cat. The cat widened its eyes and jumped back quickly, hissing at him.

"Yoru!"

The cat flinched at the tone and stopped, but seemed to sniff and pout. It walked back to her side, but this time as far away as possible from the man. She gave the cat a stern look before smiling apologetically to Akihiko, "Sorry, he's a bit antisocial towards anyone other than me. Still a baby."

He shook his head, still fascinated by the cat, "No problem… is that…?"

"Yup, Yoru's an AI! And also a nekomata~ He's so cute right?" The cat's ears twitched at the c-word, but did not counter. Akihiko chuckled in amusement,

"It seems that he does not want to be called cute, Haru. But interesting. So he's currently out as a hologram? How did you create him?"

"Hi. Mi. Tsu~ But don't tell anyone. I don't want them to dissect him."

"Alright then. Nice to meet you, Yoru."

It stared at him with indifferent eyes before nodding slightly. Then, it curled up and yawned before falling asleep. Akihiko and Haruko exchanged glances before laughing again.

"What a lazy cat, Haru."

"It takes after you, Nii-chan."

At that, a cyber message appeared. They both glanced at it.

No, I don't, Haru.

And they both laughed again at the cat's rebuke. The cat's ears merely twitched at the sound, but seemed to ignore it (though it shook from suppressing its rage).

…

Haruko was a kind, gentle girl. She was also loud and optimistic when around those who needed the noisy mirth in their lives.

And in the hospital, there were a lot of people who needed a cheerful, healthy girl support.

She was more than happy to offer it.

"Alright, kids. This is the plan…"

Haru whispered to the attentive kids; each of them with a mischievous smirk. Then at once, they ran down the large halls, flipping every skirt they saw while loudly laughing at each reaction they witnessed. The nurses immediately tried covering their undergarments that were revealed by the kids, but the men saw it and fell down with satisfied nosebleeds. Especially when there was the occasional naughty garments like garter belts, sexy black lingerie, and clear underwear that hid nothing.

It was a damn good day.

"I-I c-can die happy now… thank you, k-kids…"

A thoroughly embarrassed nurse slammed her fist into his head, puffing, "Then, just die. HARU!"

The little girl appeared immediately, saluting to the other, "Haru reporting!"

She was rewarded with a double ice-cream bump on her forehead. "Mou, I don't mind if you do pranks, but can you not include us?"

The head nurse walked in, "Isn't it alright? She's a nice girl, lifting all of the other's spirits."

Haru grinned, "Nice to be thought of that way, head nurse!"

The head nurse nodded, "Now run along, Haru."

The little girl left just as quickly as she came. The nurse looked at her boss, "Why does she gets let off so easily?"

The head just smiled softly, "Because her pranks are with good intention. And she also helps around the hospital. Haru's a nice girl that everyone needs in their life. Especially in this hospital. Did you see the faces of the women and men? They used to be so depressed and dull. Now, the whole area's filled with mirth and hopes again."

"Eh—now that you mention it, it does seem that way… But she's just a little girl; how can you be so sure?"

The head nurse shook her head, "She may be little, but her heart and mind is big. This hospital does that to people, even the young ones… And especially her. Ever since I first saw her, she has always been smiling brightly. Even when everything goes wrong and the world seems out to get her, she still strives forward. She's been here for years, born with an incurable sickness. And her parents even abandoned her because of that sickness. Her father blaming her for everything and abused her when drunk. Only having her brother to care for her, but even that boy's busy with life and can barely visit. And just last year, she found out that she can't even live past age twelve. But she's strong, even after all that, she still keeps to herself and smiles."

"…" The other nurse was silenced as she heard about the girl's story.

Outside, a little girl walks away, smile almost faltering. "I'm not that strong…"

…

That night, Akihiko rushed to the hospital ward where his little sister would be. He was about to open it, but paused when he noticed that it was silent. Opening it slightly, he watched the girl, who watched Yoru, who was inside the laptop. Game packages and magazines spread all over her bed.

She gently placed a hand on the screen, "…Yoru… even you are just an illusion… even you are not real…"

The cat whimpered as it heard her unusually quiet, solemn voice. Haru sighed as she fell back onto the bed, an arm covering her eyes as she looked up. Tears, silent long-held-back tears, trailed down from her eyes as she cried to herself, "Yoru, it's unfair. Why do I have to die in three years? Why can't I live longer and travel the world? Leave this place? Yoru… they say I'm strong… but even I don't want to die like that. The others are lucky; they only got hurt—it's not permanent like mine's! They can fight death and win! Why can't I do that? Why?

I'm scared… Yoru… Nii-chan…"

And all was silent as she cried herself to sleep. Akihiko froze and silently left.

…

Three years later, he finished creating a game. A game that he poured his heart and everything that he knew into.

Aincrad.

It was his last but best game. And half of it were Haru's designs and Haru's wishes.

Haru?

She died, just a few days ago. Died with a bright smile, but he knew better after that night three years ago… which is why he created Aincrad. It was their dream world—a floating castle in the sky, a VRMMORPG where thousands play at once, and filled with her programs that she sent all her life making because she couldn't leave the hospital to see the outside world.

And it was a world where people truly had to fight death and win. It truly was unfair if they couldn't get hurt permanently like Haru.

That day, Kayaba Akihiko smiled and cried while holding on to his new game, Sword Art Online.

…

Akihiko blinked as the swordsman figured it out, "You're Kayaba Akihiko!"

He smiled, "…yes… Curious, I thought that people will start seeing it on the 100th floor… to think you will this early…"

"Why'd you do it?!"

"…" Akihiko softened his eyes for a mere moment before being indifferent again, "…have you ever wanted to see a castle floating in the sky? Such a beautiful thing… At first, it was only for that, but it became something more later on, Kirigaya Kazuto-san."

They continued on talking before fighting once more. Akihiko smiled as he finally saw the person who introduced Haru to the world of games and illusions.

…

Akihiko laughed to himself as he fell off the castle, watching it disintegrate into little pieces. Just like Laputa, the first movie that they watched together. A girl and a boy gets together and destroys the evil guy and the whole castle.

Tears once again fell as he watched. He felt like such a crybaby ever since his little sister died… A midnight blue cat jumped off the building and descended next to him mewing. But instead, he saw the spirit behind the cat…

"Haru…"

…

It had been days since SAO was completed and the whole incident was over. Kirito glanced at Asuna, who peacefully slept. After watching her for a long time, he left passing by a familiar room. His eyes softened as he remembered a time when he was sent to the hospital. His grandfather was abusing him at that time. And his sister—cousin—was forced into kendo because of him. Something he really felt guilty about…

But at that time in the hospital, there was a little girl who cheered him up and made him want to strive forward, even with all that. Especially when he realized how she was in a worse situation than him. They got along very well; both being the first friends of each other. And she was an interesting girl, who was a genius at programming—

His eyes widened as he remembered her name and her dream.

Kayaba Haruko. Her dream was to create a castle floating in the sky.

He opened the door roughly to find an old man in the room, "A-ah, sorry. I was trying to find a little girl. She used to be in this room."

And he was about to close the door when the old man said, "Wait. Are you Haru-chan's friend?"

Kirito scratched his cheek, "…you can say that, I guess. We haven't met for a long time."

The old man nodded and handed him a laptop, "Kirito or Kirigaya Kazuto-san, right? She let me watch Sword Art Online when I had nothing to do."

"Eh? You mean—"

Once again, he nodded. "You see… Two years ago, I found this laptop underneath the bed. I'm old and can't move out of the bed so I thought that it wouldn't hurt to take a peek. And when I opened it, I saw a girl behind the screen, petting a blue nekomata. She told me that she had died a few days before and wanted to stop her brother from doing anything funny. Apparently, her older brother cared for her a lot and found it unfair how the people who didn't fight for their life everyday lived on whenever he visited the hospital. But being nothing more than a program now, she couldn't really do anything except manipulate a few stuff.

And since, she understood my boredom, she let me watch SAO live. Never gets boring. You youngsters really should understand how lucky you all were now. Playing games and wasting time while complaining about life when you had everything compared to her. Mm, since you're both friends, you should take the laptop. This old man is going to die soon anyways by the monster called old age. The last boss that will always win even when you're level 99 or whatever."

Kirito silently accepted it, still stunned by what the other said. Unconsciously, he walked out and back to where Asuna was, opening it to find a man, a little girl, and a nekomata.

The man scratched his cheek, "Yo, Kazuto-san. Seems like you found out."

The little girl cheerily smiled, "Nii-chan, of course, he did! It's Kirito! By the way, killing the laptop does nothing! We're all around the net world!"

The cat mewed, eyeing him curiously before appearing in reality as a hologram.

"Boo, Yoru! Not cool how you get to use the hologram system! Anyways, how's your girlfriend?"

Kirito blinked before turning the screen so that they saw an unconscious girl, "This wasn't any of your doing was it? I don't care what you do, but bring back Asuna now."

Akihiko sighed, "Not mine, but her fiance's. I can't do anything since her fiance's obsessed."

Haru nodded, "Trust him; he's not lying. While you two were in the game, another game was created. It's not as good as SAO though!"

Yoru nodded while mewing again. Kirito frowned, wondering why he was going to believe the murderer and his little sister...

"Tell me. I want Asuna back."

But in a way, he understood now. With Asuna unconscious, he could understand Kayaba Akihiko and his grief when his little sister died. He, himself, would do anything for Asuna.

Akihiko smiled, "Of course."

A/N: Just watched the first, maybe, 12 episodes of SAO. And I thought that Aki really wasn't that bad of a guy. I purely understand that guy... the idea of a floating castle and making fantasy real. To me, a gamer, it's romance. To be able to fight and live in a beautiful game like that... just the idea of fighting to the death in that game made me fall in love with SAO. I would play it anyday. The factor where people can die just makes the thrill all the more real. Like sky-diving and bungee-jumping and camping. Three of my favorite games in reality. Completely do not understand the gamers in episode 1, who panicked like that. Real gamers wouldn't. So what if you can die in a game? You can die in reality anyday like little Haru.

Ah. I named Haru after a season. Aki from Akihiko meant Fall/Autumn (or at least the hiragana 'aki' does. The real kanji of his name doesn't refer to the season). So I thought it would be fitting for Haruko to be named after Haru (spring).