Disclaimer: I don't own Yu-Gi-Oh or any characters therein.

A/N: Warning: Hints of what can be taken as either Relyshipping…or just Shizuka's big brother complex.

..Melted Triangle

Shizuka had always loved her big brother.

Relatives used to laugh when they were younger, finding it adorable that whatever Katsuya did, little Shizuka copied. When Katsuya laughed, so did she. When he fell down, so did she. When he started fist-fighting with a child twice his size, well, so did she, and that one didn't make their family laugh as much.

Katsuya had plenty of affection for his little sister, and always gave her his full attention. They didn't really have any other friends. They didn't need any other friends. When they got bored and wanted to play, when their parents started fighting again, or when a tutor or audience was needed for homework, they went to each other and each other only.

Then one day, when Shizuka was eight years old and her brother nine, things changed.

A moving truck became omnipresent in the driveway of the previously empty house next door. The two watched in fascination as the most bizarre items were unloaded from it and brought inside-an ancient chair wrought in gold, boxes of strange jewelry, a golden lioness with eyes of blue stone. Through the grapevine they discovered that their new neighbors were an archeologist specializing in artifacts from ancient Egypt, his wife, and their two young children.

It was the 'two young children' bit that caught Katsuya's attention. The only other kids in the neighborhood up until that point were already teenagers, and it might be fun to have some people closer to his age to play with.

So he decided to go over and say hello.

Shizuka, naturally, followed.

The door was answered by a slip of a boy with big brown eyes and hair that Katsuya would later describe as "fluffy". Timidly he asked who they were.

"We're your new neighbors," Shizuka explained shyly.

"Yeah," Katsuya put in. "We came to meet…" His eyes drifted to a spot over the boy's shoulder and widened. His voice trailed off.

Confused, Shizuka followed her brother's gaze to see a girl, head poking curiously around the hallway wall to see who the visitors were. She was skinny and pale, with light hair and warm-colored eyes that made her look much like the boy who'd opened the door, only female (which admittedly wasn't much of a leap).

Having been noticed, the girl came forward with a smile. "Hi!" she chirped. "So you're our neighbors, huh?"

Katsuya managed a nod. Shizuka was startled to notice that his face was turning red.

The girl noticed it as well and giggled. "I like you," she announced. "Let's be friends!" A wide smile revealed a missing front tooth.

"I'm Katsuya Jonouchi," Katsuya said, finding his voice again. "This is my little sister Shizuka."

Shizuka nodded politely, not sure why she suddenly felt so uneasy.

"My name's Amane," the girl replied. "Amane Bakura. And Shy Guy here is my brother Ryo. We're twins, but I'm the oldest."

"By twelve minutes," Ryo pointed out softly.

"Still the oldest," she retorted before turning back to the visitors. "You guys wanna come in? Mom and Dad won't mind."

Shizuka saw her brother's lips part to form the word 'yes' and hurried to speak first.

"I'm sorry," she said, "but our parents wanted us to come right home." She ignored both the confused-and disappointed-look Katsuya sent her, and the resulting feeling of guilt.

"That's okay," Amane said, undeterred. "You can come back tomorrow, since it's the weekend, and we can play then!"

"I'll be there!" Katsuya promised, grinning again. Shizuka blinked at the use of 'I' instead of 'we' but said nothing.

Plans made, the group said their goodbyes (rather, Katsuya and Amane said goodbye while Shizuka and Ryo shifted awkwardly back and forth), and the Jonouchi siblings headed back home.

"Why'd you say Mom and Dad wanted us to come back right away?" Katsuya asked as soon as they'd gotten inside. "They didn't say that."

Shizuka shrugged uncomfortably. "I…I wanted to come home, big brother." I wanted to play with you by myself, she added silently.

"Are you okay?" he asked, expression changing from irritation to concern. "You're not sick or anything, right?"

She smiled, happy that she had his attention back. "I'm fine." I'm fine now.

..

The next day Katsuya went to the house next door, as promised. Only somewhat reluctantly, Shizuka went along.

Amane flung the door open before they had so much as knocked. "You came!" she exclaimed happily. "I was waiting!"

"I never break a promise," Katsuya said proudly. Shizuka hid a grin. That was one of the things her big brother liked to say when he was trying to act cool.

Wait. Big brother only acts cool if he's trying to impress somebody special. Shizuka's stomach twisted. Why would he want to impress the new neighbor? What's so special about her?

In any case, Amane wasn't even looking at Katsuya anymore. She was looking at Shizuka with a strange expression on her face.

Shizuka didn't like being stared at. She fidgeted and searched for a way to take the other girl's attention off of her; it didn't take long.

"Amane-kun," she asked hesitantly, "um, why are you wearing a swimsuit?"

It was true; the girl was wearing a turquoise one-piece swimsuit and her hair pulled up, as if it were summer and not the middle of spring. Certainly, the weather had been warm enough to go out without putting on a coat, but it was still chilly enough to classify anyone dressed as Amane was as either masochistic or insane.

"Oh, this," Amane said, looking down at her ensemble. "I thought it'd be fun to play Water Tag! That's my favorite game to play outside, 'specially in the summer."

"Isn't Water Tag…um…supposed to be only in the summer?" Shizuka couldn't help asking.

Amane shrugged. "Maybe," she responded. "But summer's coming too slow this year, so I'm gonna call it out by dressing and playing for warm weather!"

Shizuka, perplexed, decided that the reasoning must have sounded much more sensible inside the girl's head.

Katsuya, however, exclaimed "I'm in!"

Shizuka turned to him in horror. "You didn't even bring a swimsuit, big brother," she protested.

"I can take the shirt off," Katsuya figured. "An' what's the worst Mom can do if I get my shorts wet?"

Shizuka still didn't think it was a good idea. They would probably all end up getting sick.

But then Katsuya pulled off his shirt and asked Amane if she wanted to race to the backyard, so Shizuka quieted her objections and ran after them.

..

A week. That was all it took for life to turn upside-down.

The Water Tag game took place on a Saturday (for the record, Shizuka and Katsuya did end up with colds, although Amane seemed fine). By the next Saturday, the changes were apparent enough that Shizuka couldn't ignore them anymore.

The incident that really shook things up occurred on a Thursday. She was doing her math homework at the kitchen table, leaving the hardest problems for later as she always did, because Katsuya would always help her with them when she asked.

Her brother came bounding downstairs just as she'd finished up with the rest of the page. "Big brother," she called, slipping off her chair and grabbing the paper. "I need some help with my homework."

Katsuya already had one foot out the door by the time the last syllable had fallen from Shizuka's lips. "Sorry, sis," he said, ruffling her hair absently. "I wanted to visit Amane today. I'll help you another time, okay?"

Before she could either confirm or deny whether everything really was "okay", her brother was gone, the door closed behind him.

Perplexed and a little hurt, Shizuka returned to the kitchen and did some thinking. What she came up with was nothing short of obvious: Her brother was infatuated with a girl. A girl that…wasn't her.

It didn't seem fair. Shizuka and Katsuya had had a special bond since the former's birth, and they'd always been there for each other. Shizuka didn't need (or want) anyone else, and up till now she'd thought her brother felt the same.

Now this complete stranger had shown up out of nowhere and changed everything.

Not for the first time, Shizuka's shoulders slumped as she wondered why the new girl was so special.

And she tried to ignore the nasty voice in the back of her mind-the one that whispered that she was being replaced.

..

Math was impossible after that; all of her concentration had gone down the drain. Finally deciding there was nothing else for it, Shizuka made her way to the Bakura residence.

Ryo answered the door again. "Hello," was all he managed to get out before turning away and coughing. "Sorry," he said upon reappearance, "I've been sick. You're looking for your brother and my sister, aren't you?"

She nodded.

"They're in the back."

Shizuka thanked him and proceeded to the backyard, where she found Katsuya and Amane sword fighting with sticks.

Amane noticed her first. The pale-haired girl's fierce, dramatic expression fell off her face like a mask as she gave Shizuka an energetic wave and a huge smile. "Hi, Shizuka-chan!"

Shizuka tried to be polite and not bristle at the "-chan" honorific.

"Hey, sis," Katsuya greeted her. "What're you doing here?"

She shrugged in reply.

"Wanna play Pirates with us?" Amane asked. "I'm Blackbeard, and Katsuya's Redbeard. You could be Whitebeard or something?"

Shizuka didn't hear Amane's last comment. Katsuya. Katsuya. She's calling big brother by his first name when they barely know each other.

"Shizuka-chan?"

The voice was Amane's once more, and it was a little worried. Shizuka snapped out of it, put a smile on her face and said "I'll be Whitebeard. That sounds good."

"You'll have to have a sword," Amane remarked. "Go inside and ask Ryo where my bedroom is. There're a bunch of great sticks right by the door." At Shizuka's confused look, Amane laughed. "You didn't think I just found these sticks lying around, did you? I keep them for special occasions, like new friends coming over to swordfight!"

Having been chastised by yet another dose of Amane Logic, Shizuka obeyed and went back to the door. Ryo pointed to Amane's bedroom door, where Shizuka found the sticks right where they were supposed to be.

A giggle rose up and floated through the open bedroom window. A distinctly Amane-ish giggle. Interested, Shizuka went to said window and looked down to see just what was so funny.

Katsuya blushing furiously. Amane, looking for all the world as if she was being told a very funny joke. That expression faded alarmingly fast once Katsuya said something else-Shizuka couldn't hear it from this distance, but she could certainly guess.

The sticks fell from her arms. She didn't bother to pick them up; she simply left the room, left the house, and ran home.

..

It was official then, an utterly miserable Shizuka realized as she sat on her bed in tears. She had been replaced by the new girl next door. Just thinking it was enough to make her start crying again.

Katsuya had known her-loved her-for eight years, since the day she was born. And she loved him more than anybody. So how on earth had Amane managed to destroy all that in just a few days?

She couldn't find any good answer.

When Katsuya came home awhile later and asked why she'd left, if she was alright, Shizuka did something she couldn't remember doing before.

She ignored him.

..

On that Saturday, fed up with receiving the silent treatment from his little sister, Katsuya went out for a walk. Amane stopped by during his absence.

"Hey," she greeted Shizuka when the door opened. "Can I talk to you for a second?"

Already kicking herself for answering the door in the first place, Shizuka stepped back and allowed the other girl entry.

Amane got straight to the point. "Why do you hate me?"

Shizuka blinked, taken aback. "Hate-? I don't…I don't hate you." She had never really hated anyone in her life, and she didn't know if she could.

"Good," Amane said, looking relieved. "'Cause I don't hate you either." She took a small step closer. "Actually, I really like you. A lot."

The girl's light skin had turned a burning shade of pink, and before Shizuka could properly register this (or the words that had just been spoken), Amane had taken two more small steps and kissed her on the forehead.

Shock kept Shizuka frozen in place for exactly six seconds. A dog then barked outside and the two girls jumped apart as if scalded.

Amane spoke first. "So-"

"No," Shizuka interrupted. She shook her head for emphasis. "I don't…" Her mind was whirling like an expertly spun top, and it had nothing to do with the head shaking.

"I said I didn't hate you," she finally got out. "And I don't. But I don't think I like you."

Shizuka mentally winced at how harsh that sounded, but she pressed on, determined to speak her mind. "I don't like you because you're taking my brother away from me, even if you're not trying to do it. All Katsuya ever talks about is you. All he ever thinks about is you." Her eyes burned and her voice grew softer. "He used to think about me."

Silence. A long-seeming silence that in reality only lasted a couple of seconds.

"Okay," Amane said, startling the other girl. "That makes sense. So that's why you're always angry around me?"

Shizuka nodded.

"Okay," Amane repeated. "I guess I'll leave you alone then. I can't just dump your brother as a friend, but I'm not about to kiss him or anything." She wrinkled her nose in a way that Shizuka realized was bizarrely…cute. (No wonder her brother was so hung up-girls who could actually make their noses wrinkle and look that cute were rare, in her experience.)

Amane let herself out. Just before closing the door she added, "Sorry about your brother. Really." She gave a little smile. "Hope I see you around, Shizuka-chan."

The door closed. Shizuka brought a hand to her cheek and quickly withdrew it, disliking the heat she felt there.

She was so confused. What had Amane done to her?

..

Shizuka had always loved her big brother. But she had long since dropped the habit of copying whatever Katsuya did.

At least…she'd thought so.

Maybe the habit wasn't so dead after all.

..Fin