Disclaimer: I don't own Kingdom Hearts. But I do own an AMAZING Kingdom Hearts shirt!

Pairings: RikuSora

A/N: This was inspired by KH2's Atlantica. Just look at how Sora and Ariel dance. I mean really. Hahaha. I thought of the summary and I had to write out the idea. It gets a little off around the end, but oh well.

Due to the intimacy of their friendship, Kairi had formed the habit of walking into Sora's house unannounced. His mother, a bright and warm individual, welcomed the girl with food, tea, a smile, and directions to Sora's current location.

Kairi had also taken it upon herself to lend Sora notes in class, select a college for him to attend in later years (after all, so much time away from school set her, Sora, and Riku back from the rest of their island friends), and assist him in finding a girlfriend whom he would later marry and have bundles of children with.

Kairi liked to think of herself as Sora's keeper.

And so, it was on one fine, sunny afternoon when Kairi decided it was time for Sora to awaken and embrace the day, and perhaps embark on an epic shopping excursion. She bowled through the door, smiling like a maniac, sweat dripping down her face and neck from her morning swim, jog, and obstacle course (Kairi had also taken it upon herself to become as fit as possible, just in case the Worlds fell into turmoil yet again). Sora's mother called a "Good morning!" from the kitchen, which radiated the scent of eggs and bacon.

"Good morning, Ms. Hikari!" Kairi returned, heading quite resolvedly to the staircase. She sprinted up the stairs, threw open Sora's bedroom door dramatically, and shouted, "Good morning, sleepyhead!"

Sora remained unaffected, curled into his covers, spiky hair the only evidence that he was in the bed at all. Kairi huffed and leapt onto the bed, followed immediately by Sora sitting upright in a rush, knocking heads with Kairi, yelping, and then falling back down onto his pillow. His face contorted in pain but his eyes weren't too keen on opening fully.

Something shifted in the bed beside the bewildered brunette, and a mane of silver emerged from beneath the blankets. A shirtless Riku sat up, glaring torturous death at Kairi, who merely smiled and waved.

"I didn't know you slept over, Riku!" she chirped. Sora yawned loudly.

"I didn't know you had plans for today, Kairi," he mumbled. Kairi returned her attention to him at once.

"Spur of the moment! I've only just decided." She laughed nervously as her peripheral vision revealed that Riku was still glowering in her direction. She rolled over, flopping down in the small space between her two best friends. "So! I was thinking we could go shopping, get some sea-salt ice cream – I know you've acquired a taste for that, since Roxas and all – and then maybe hit the beach and watch the sunset!" She paused, sensing a general disinterest. "What do you guys think about that?"

Riku had turned over on his side and was watching Sora intently. Sora was burrowing beneath the covers; Kairi caught a glimpse of bare skin as he pulled the nearest blanket over his head.

"Whatever you want, Kairi," he muttered sleepily. "Jus' five more minutes."

But Kairi hadn't heard his reply. She raised a flawlessly groomed eyebrow. "Why are you both shirtless?"

Sora's facial expression was hidden, but she felt him jump as though startled. At least he was awake now. Riku was lying on his back again, staring nonchalantly at the ceiling.

"Lotsa guys sleep shirtless, Kairi," explained the older boy, not missing a beat. Kairi frowned, disappointed. Wriggling free of the boys, she hopped to her feet and gazed down at them reproachfully.

"Fine, then. I'll give you ten minutes to get ready. If you're not dressed by then, too bad, 'cause I'll be coming up to check on you!" she announced, and then she bounded cheerfully down the stairs.

Sora fell out of bed and frantically searched the messy floor for clean clothes.

Kairi grinned triumphantly as Sora's bedroom door slammed shut and figures shuffled fervently behind it. Sauntering into the living room, she sought out her favorite armchair and made to lounge in it when Ms. Hikari's voice graced the room.

"Kairi, dear, would you mind running out and grabbing the mail for me?"

"No problem, Ms. H!" Kairi bounced to her feet and reached for the doorknob.

"Thank you, dear. It's just that Sora gets so much mail now."

With a raised eyebrow, Kairi hurried for the mailbox at the end of the flower-lined driveway. Carelessly throwing it open, she found that there was indeed a stack of mail, though not as much as she had anticipated. She sifted through it as she stumbled back toward the house.

Indeed, most of the mail was for Sora. Peter Pan, Donald Duck, Goofy, Aladdin, Hayner, Pence…and then a bright pink envelope caught her eye, and Kairi noted with interest that it was from a girl. A girl named Ariel. She made a thoughtful noise and fell back on her beloved armchair to read it.

"Dear Sora," Kairi read aloud to herself, "So sorry I haven't written in awhile. I've had a lot to do around the castle lately. I do miss you, though, and I hope that maybe we could meet sometime to catch up. I hope to hear from you soon." She hadn't realized her face had morphed into a very disgusted glare until she noticed how much her lack of background information infuriated her. Tossing the letters lazily onto the coffee table, she stomped back up the stairs and marched right into Sora's bedroom, promptly locking eyes with the panicked brunette.

"Kairi, what are you doing?! It's only been five minutes! Get out! I'm half naked!" he shrieked, face reddening. But Kairi hadn't noticed his half-naked-ness, nor had she noticed the peculiar way he and Riku had jumped away from each other.

"Who is Ariel?" she asked. Sora looked confused for a moment. "Ah-ah, I won't have any of that! I want details!"

"Oh, Atlantica. We just sang and stuff. Look, Kairi, I think you should let us get dressed now."

"…and stuff?" Kairi persisted. The veil of curiosity was lifted from her eyes, however, and she was suddenly aware of being in a room with two harassed, half-naked teenage boys. She whirled around and exited the room in a very embarrassed fashion.

"She's insane."

"Yeah, well, at least she doesn't suspect anything."

Downstairs, Kairi gathered her thoughts as she paced the living room. She knew three things: One, Ariel was from another world, one called Atlantica; two, Sora was well acquainted with this female, enough for Ariel to address him so informally; and three, Sora was going to see Ariel soon, and perhaps for a date. She was horrorstruck at this notion; how could Sora date someone she hadn't set him up with? She crossed her arms over her chest, a smirk slithering onto her face. She wouldn't be a good friend if she let Sora go on a date with someone she didn't know every detail about. She would have to dig up the information, and she knew exactly what she was going to do.

Cloaked by darkness, Kairi maneuvered surreptitiously up the driveway of the Hikari home. The moon illuminated the resolve burning in her eyes, and then she was gone, returned to the cover of shadow as she slipped through the front door.

She may not be a keyblade master, but Kairi had a few abilities of her own which she had been dying to put to use. Naminé was a part of her, now – they were whole – and Naminé had dominion over memories. Kairi knew that all she had to do was sneak a peak at Sora's memories of the unknown female Ariel.

The ninja redhead crept up the stairs, careful to avoid any creaky steps, and then silently wisped into Sora's bedroom.

Sora lie asleep peacefully; he was dead as a rock in his sleep, Kairi knew. As she hovered soundlessly above him, she also realized that this was too easy. And as soon as she came to this realization, a cold hand clamped over her mouth and a pair of strong arms carried her out of the room. She didn't scream, for fear of waking Sora, but as soon as she and her captor were in the hall, she elbowed him in what she hoped was the stomach and bit his hand.

Riku howled in pain and released Kairi in favor of cradling his hand. Kairi's eyes widened in surprise and amusement and she covered her mouth with her hands to muffle her rising laughter.

"Riku!" she whispered. "I'm sorry, I had no idea! What are you doing here?"

Riku rolled his eyes. "I should be asking you the same."

Kairi blushed and stood erect. "W-well!"

Riku turned and started down the stairs, gesturing her to follow. She did so and was led into the kitchen, where Riku poured her a glass of orange juice and waited expectantly for her excuse.

Kairi sheepishly eyed him over the rim of the glass as she slouched over on the stool.

"I…errr…" She couldn't think of any lies, and she figured that Riku would probably be able to tell she was lying anyway. A wave of female intuition passed over her, and she discerned that Riku might very well be just as interested in the identity of Ariel as she was. "Well," she began, pausing meaningfully, "I have ascertained that Sora is seeing someone."

For a moment, Riku's face was comparable to a trembling deer caught in the headlights of a very large semi-truck. He started to say something, but it came out a nonsensical stutter. Calmly, he shut his mouth, took a deep breath, and asked, "Who?"

Kairi giggled inwardly, then swept into the living room. She returned with an opened pink letter. "This tells exactly who."

Bemused, Riku took the letter. He examined it skeptically, then looked at Kairi with a raised eyebrow. "You were reading Sora's mail?"

Kairi shrugged and waved it off. "We're best friends." She seemed disappointed at Riku's hesitance to invade Sora's privacy. "Well? Read it already! It's from his new girlfriend."

Riku appeared torn for a few seconds, and then he shrugged and opened the letter. He read it quickly and with complete indifference handed it back to Kairi.

"This doesn't prove anything. Sora made a lot of friends in the worlds he visited," he dismissed.

"Exactly," said Kairi, a certain gleam in her eye. "I bet he made a lot of friends."

Riku scoffed. "It's none of our business, anyway, Kairi. Sora would tell us if he was with someone, and even if he didn't, we should respect his privacy."

Kairi looked affronted.

"Are you really going to let him go on a date with some girl we know nothing about? What if she…what if she rapes him?!" she argued. She huffed and started for the staircase again. "Well, anyway, I'm looking out for Sora and I'm going to find out just who she is."

Riku followed her. "And how do you think you're going to do that?"

"Easy," Kairi shrugged. "Naminé could poke around in Sora's memories, and Naminé is me, so…so can I." She felt victorious when Riku fell silent.

Kneeling at Sora's bedside, Kairi placed her hand on the sleeping boy's forehead and shut her eyes. She concentrated deeply, watched attentively by Riku.

Dancing. Dancing and singing. Why was Sora dancing with this girl? Kairi knew right away that the mermaid with shocking red hair was Ariel. But as she watched, she found that Ariel was with someone, a guy named Eric. She sneaked a peek at Riku, who was patiently waiting for her to finish.

She wanted to lead Riku on; she couldn't let him think of her as silly and melodramatic. She opened her eyes and peered gravely at Riku, then shuffled him back into the kitchen.

"Well, Miss Snoop?" Riku asked expectantly.

Kairi felt another wave of female intuition. Riku was trying to hide it, but he wanted to know. She knew it. And, wait, why was he at Sora's house again? Why did he never have his shirt on when he was over? Why didn't Sora ever think to wear a shirt? Why did the two of them sleep until afternoon – what were they doing all night? Why did Riku look so guilty when Kairi had mentioned Sora being with someone? And…why hadn't she realized the way Riku was looking at Sora this morning? Why hadn't she realized how ruffled and awkward the boys had appeared when she entered the room unannounced, how they had darted apart, as though they'd been…Why hadn't she remembered Sora and Riku's history, how Sora had fallen to his knees in relief of finding Riku, when all Kairi got was a hug?

"Oh, my."

"'Oh my' what?" Riku asked. Kairi awoke from her fangirl fantasies and possibly-too-much-read-into recollections.

Kairi adopted a sly grin. "Wouldn't you like to know?"

Riku started off in the direction of the staircase. "If you're going to be difficult, then I won't bother asking like I know you want me to."

Kairi pouted, but she caught the way he glanced back at her almost hopefully. She leaned leisurely against the kitchen counter, pretending to thoughtfully examine her nails.

"Well," she drawled, "Ariel is very pretty."

Riku knew she was up to something, but couldn't quite tell what it was yet. He watched the redhead cautiously.

"Sora was singing with her. And dancing. Dancing happily, dancing closely." Kairi watched for Riku's reaction in her peripheral vision. Riku was definitely interested. She approached him and held out her hand. "Here, I can show you."

Riku hesitantly took her hand. He saw flashes of a redheaded mermaid dancing with Sora, and then Kairi released his hand.

"Interesting, right?" she asked. It was a challenge. Riku didn't meet her eyes. He glanced up toward Sora's room.

"It's his business," he said, a hint of urgency in his tone. Kairi placed her hands on her hips.

"Oh, is it? I suppose he wouldn't have to tell you…it's not like you'd be jealous or anything."

Riku's eyes snapped into lock with Kairi's. "Why would you say that?"

Kairi shrugged and looked around the counter for her glass of unfinished orange juice. Taking it into her hands, she sighed. "No reason. I wonder why he didn't tell you, though. Makes you wonder what else he was up to. Guess you better go ask him."

Riku was already thundering up the stairs.

Kairi laughed and ran up after him. Riku was gently waking Sora, then pestering him fervently about Ariel. Sora was puzzled for awhile, then as realization set in, he smiled.

"Oh, Riku. She's just my friend. She needed help in a musical. She's with Prince Eric, though. They're married." He gave Riku a quick kiss on the cheek.

Riku blanched. Kairi gasped from the doorway, and when Sora realized she was there, it was his turn to pale. "K-Kairi?"

"Aha! I knew it! It was kinda funny how Riku's always staying the night over here. And looking at you all…googly." Riku's eyes went wide in terror. "What were you two up to before I walked in this morning?"

"When did you know?" Riku asked. Kairi smiled insanely.

"I had an epiphany a few minutes ago." She glared at the pair patronizingly. "Why did you keep it a secret?!"

"I was afraid you'd freak out," Sora replied quietly.

"Freak out?!" Kairi exclaimed. "I was freaking out when you received a letter from a mysterious woman! I wouldn't have had to worry so much and go through the effort of sneaking into your house in the middle of the night if you two had just told me you're together!"

Riku's eyebrow twitched. "You didn't have to do that anyway."

Kairi waved her hand dismissively. "Don't be ridiculous. Sora's like my little brother. It's my job to interfere in his life." She climbed into Sora's bed, lying between the boys, and she lifted their hands and placed them together. "Remember?" she asked.

Sora and Riku smiled. "Yeah."

"Don't ever worry about my reaction. I'll always love you both, no matter what. I'm actually relieved you're together. Now I don't have to worry about either of you."

Riku kissed the top of Kairi's head and Sora awkwardly reached around to hug her. "Thanks, Kairi."

The warm moment was accompanied by relative silence, until Kairi spoke again.

"But you do realize that I'm coming with you when you visit Ariel, right?"