Summary: Rin and Len get into another childish fight.

AN: Sorry for the delay. I actually planned on doing a Soundless Voice/Proof of Life based chapter this time, but I'm a bit stuck, so I figured I'd do something lighter and easier meanwhile. It will be next, if I can finish it.

This one's loosely based off of "Taisetsu na Kotoba" (Important Words). The PV for it was just so inexplicably adorable to me... These two really do have the cutest relationship!! I was sad that the end wasn't fluffier though...

Anyway, I'll update again when I have at least 15 reviews. Thanks for all the positive feedback, everyone! I apologize that this chapter is also somewhat lacking in fluff. It seems like small kisses and hugs are as fluffy as I can get... I'm too embarrassed to write things that aren't relatively platonic in nature...

"Stupid Len!"

"Stupid Rin!"

"I HATE YOU!"

Rin pulled down an eyelid and Len yanked out the corner of his mouth. After making these unattractive, immature faces at each other, both stormed off to their respective rooms.

It had been a pretty good birthday for the mirrored Vocaloids up until this point. Meiko promised not to get drunk, Kaito managed to keep his hands off the cake until the Kagamines had blown out their candles, Miku hadn't slipped leeks into the frosting, and Luka hadn't brutally injured Gakupo... yet, anyway.

Finally, slices of cake were passed around, and everyone was sitting around the table, offering their congratulations to the youngest pair of their 'family'. Since they somehow ended up one chair short, Rin and Len shared a chair (Luka vehemently refused to sit on Gakupo's lap like he had offered). The two were used to being close to each other, anyway.

But then somehow, heck broke loose.

"H-hey! Don't eat my cake, you have your own!" Len suddenly snapped, startling the party's peaceful atmosphere.

"I just took a small bite because yours had more frosting on it!" Rin protested defensively, chewing on her stolen goods.

"A SMALL bite?! Half of my freakin' piece is gone!!"

Meiko quickly tried to mediate before things escalated, but she went unheard as the blondes continued to bicker. "Now, now, you two, it's just cake, and there's plenty more left..."

"AH...! M-MY STRAWBERRY!" Rin wailed as Len swooped in with his fork. "GIVE IT BAAACK!"

Though usually the more grown-up of the two, today Len displayed a rare streak of immaturity. He very deliberately licked the fruit and offered it to his furious partner. "Here, want it now?"

The girl's brows scrunched up, and she shoved him, almost knocking him off the chair in the process. "Ewww, no! Get away, you retard!"

Len smartly recovered from the push by making a grab for the table cloth. "Who are you calling retard?!" he shouted with the strawberry in his mouth (which made distinguishing his sentence quite a task). "You're so rude and uncute!"

The other Vocaloids watched with a silent, reverent sort of horror as the argument continued to unfold. Even Meiko had given up on intervening. (Only Kaito continued to nibble at his cake, but his eyes never left the twins, and he chewed a little more slowly and quietly, as if to keep a bomb from going off.)

"You're the uncute one, retard!" Rin shot back with an ever-growing scowl on her face.

"You could stand to learn some manners! Like — like Miku-nee!!" Len pointed in the leek-lover's direction.

Miku flinched at suddenly being dragged into the conversation. She put up two dainty hands and began softly, "Well, Rin-chan has plenty of good—" But as suddenly as Miku was dragged into the conversation, the Kagamines booted her out again and continued with their arguing. She trailed off pathetically and returned to observation mode.

"Retarded!"

"Uncute!"

"Whiny!"

"Rude!"

"Shota!"

"Selfish!"

"Stupid Len!"

"Stupid Rin!"

And then to end the insult battle, both screamed as loudly as they could...

"I HATE YOU!"

Here is where they exchanged ugly faces and ran off to their bedrooms.

The remaining Vocaloids sat with their mouths agape, feeling as though they had just witnessed a full-scale war in a three minute time span. It took a while before anyone dared to comment on what had occurred.

Kaito tentatively started, first swallowing his cake. "I... I guess this would be a bad time to open the presents, huh?"

Gakupo began to fan himself furiously, as though releasing all his pent-up worry. "Goodness, what a horrible sight! I certainly hope Len-dono and Rin-dono make up soon..."

Meiko groaned and leaned back in her chair, trying not to think about the work she had put into making this party a nice one, all in vain. "Can I get drunk yet?"

Miku twirled the ends of her ponytails around, looking sad and confused. "Those two... why do they have to get riled up so easily...?"

Luka was the only one who didn't immediately have some kind of comment, but her face clearly displayed a pensive and concerned expression. After a long pause, she finally said, "I'm sure they'll make up."

Everyone's attention shifted over to Luka. Four questioning pairs of eyes gazed at the pink-haired woman.

"I mean... those two are too close to be fighting for very long."

"That's true..." the group mumbled in agreement. Everyone tried to continue to be jovial for whenever Rin and Len decided to cool down and return to the party.

"Ahhh... man... why'd I have to start such a fuss..." Inside her bedroom, Rin clutched a pillow tightly to her chest. She was replaying the fight in her mind and realizing it would have all been avoided if she hadn't touched Len's cake in the first place. Already, she felt guilty. "I shouldn't have called Len retarded, either... I'm actually envious of how smart he is..."

With a sigh, she set her pillow aside and approached her mirror. "Len," she said quietly, rehearsing to her reflection. "I'm really, really sorry... I didn't mean those things I said..."

Rin summoned some of her best crocodile tears, and her bottom lip trembled pathetically. "So... so please forgive me..." She nodded approvingly at herself. "Okay, I've gotta go apologize to him now!"

"Agh, why did I lose my temper like that?!" Len punched a fist into his pillow, but all of his frustration quickly faded away. His shoulders loosened as he laid down on the pillow he had just been abusing. He, too, was thinking about the fight. "If I hadn't reacted the way I did, she wouldn't have gotten mad and we wouldn have never started fighting... She didn't really eat that much of my cake..."

Len recalled all the nasty insults he had shot at Rin. "Agh, why did I say those kinds of things to her?! Rin's not really rude... she's always looking out for me... And she has a lot of cute points... she's so protective and thoughtful... and she always knows when I'm feeling down... and she has nice eyes..."

He paused and blushed. "Wait, no, that doesn't have anything to do with it..." Brusquely shaking his head back and forth, he stood up and walked over to his mirror. After smoothing down a cowlick, he cleared his throat and stared intently at his reflection. "Listen, Rin... I'm sorry for losing my temper. I got carried away and said a bunch of untrue stuff... can you forgive me?"

Almost forgetting that he was addressing himself (after all, his reflection did look a great deal like Rin anyway), he waited for a response for a moment before he said to himself, "That should work... I'm gonna go apologize right away...!"

Rin slammed open her door, and Len's slammed open in unison. They approached each other, both tense and somewhat out of breath.

There's Rin...!

L-Len! Now's my chance!

Rin wrung her hands together and tried to put on her 'I-am-so-pathetic-please-go-easy-on-me' face, but she was so flustered that she couldn't remember how to change her expressions. Len ran his hands through his hair, rubbed his nose, and shifted his weight around like crazy, but couldn't seem to find a position that was suitable for apologizing. Both paused, waiting to see who would have the courage to talk first, but they got impatient and ended up starting at the same time.

"Len, I have something I want to talk to you about—"
"Rin, I want to talk to you about this whole thing—"

"I didn't mean a word of it—"
"I can't believe I said the things I said—"

"You're my best friend, and I don't want to hurt you—"
"The truth is, I really do care about you—"

"What I'm trying to say is—"
"Anyway, the point is—"

"I'M SORRY!"

True to their last names, Rin and Len really did do everything the same way. The real apology was not very different than their rehearsals in front of the mirror, because both opened their eyes, both wore the same perplexed (but happy) expressions, and both ran forward for a hug at the same time. The comfort of each others' arms seemed to serve as a reminder that life was best when they were on good terms.

As for the rest of the Vocaloids, they had heard the doors open and poked their heads around the hallway corner to see what would ensue. Once the bickering pair had embraced, everyone had to hold back an 'awww' for fear that they'd be caught spying, so they scrambled back to the kitchen and waited for the Kagamines. Sure enough, the twins appeared in the kitchen entryway moments later, hand in hand.

"Can we open presents now?" they both chirped with the exact same smile on their faces.