Hah. Okay, there isn't really a plot to this. It's just a conversation between Tamaki and Kyouya, with clear romantic overtones. (Since when has any of my writing been clear?) ...And a vague, barely-there parallel with the Naruto fic Lies by Leviticus Lied.
It began with a very simple question.

"Kyouya, do you believe in true love?"

Kyouya didn't look up from his notebook. "No."

Tamaki set down the magazine that declared, 'Find Your One True Love with This Simple Quiz'. He asked, "You really don't?"

"I do not. Really." Kyouya was sitting at his low table, scribbling through whatever club business needed to be done.

Tamaki was stretched out on the soft couch, helping Kyouya. He said fervently, "You don't think that you'll ever fall in love?"

Kyouya's face remained blank, as it always did when he attempted to explain a portion of his view of Life, the Universe, and Everything to Tamaki. "According to statistics, I will fall in love eight point three times. I do not believe that any one of those eight point three people will be truer than another."

Tamaki pouted, but brightened immediately. "Well, there's this quiz in here, and I filled it out and got a sixty-two so my true love will be a sixty-two, also."

Kyouya's voice was clipped as he pointed out, "If the population of the world is six billion, and each score is attained an equal amount of times, each by one person, then you have sixty million possible true loves waiting for you. I suggest you begin exploring them immediately."

Tamaki said, "Of course I would want a girl…"

"Thirty million."

"Who speaks Japanese."

"Sixty thousand."

"Our age."

"Twenty thousand. You have genuine ambition, Tamaki."

Tamaki sniffled. "Sometimes, you make me sad, Kyouya…"

"I apologize. I am merely stating the facts."

Tamaki sat up with renewed vigor. "Kyouya, I'm going to do the quiz for you and see what you get!"

One eyebrow rose, and Kyouya fixed his glasses. "What will that prove?"

"It'll definitely prove something!" Tamaki shouted as he filled in the boxes of the right answers with a different color pen.

Kyouya asked, "What makes you think that you know me well enough to answer for me?"

Tamaki smiled, even as he diligently colored. "You're not exactly a difficult guy to know, Kyouya."

Kyouya didn't say aloud that he had received very opposite comments all his life.

Tamaki continued, "Your favorite color is dark blue, and you would keep a cat if Fuyumi-nee-chan wasn't allergic, and you're only polite if you want to be, and you're a very kind person but you try to cover that up because you play the role of the third son trying to prove himself to his father, and you scored sixty-two."

Kyouya stared at him.

Tamaki grinned as if he hadn't just breezed through most of Kyouya's personality in five seconds. "Kyouya, you're my true love!"

Kyouya turned back to his notebook. "That thing is inaccurate. For example, fill out the answers for Haruhi."

There was a pause. "She got a thiry-six."

Kyouya asked, "Doesn't that tell you something?"

Tamaki looked like a puppy, wanting to give the right answer but unable to do so. "No…"

Kyouya sighed. "Then what do you get for Hikaru?"

"…A thirty-six…" Tamaki said tentatively.

"And Kaoru?"

"…Thirty-seven…" the blond said, but then added, "And there's a note: 'Be careful! A thirty-seven is very prone to mistaking a thirty-six for their true love, but it just isn't meant to be."

Kyouya was staring at Tamaki again. "What does that mean to you?"

Tamaki frowned. "So Hikaru is going to fall in love with my daughter, as will Kaoru, but with disastrous results? Serves them right! No one should touch my daughter!"

Interesting that Tamaki was fine with calling another boy his true love, but did not even consider that Kaoru might be attracted to Hikaru. Kyouya was mildly curious by now. "Hunny and Mori?"

Tamaki obediently went to work, scrawling on the now-cluttered pages. He answered, "They both got ninety-fours."

Kyouya sat deep in thought. After a moment, he said, "I will reconcile my statistics with your quiz. The quiz gives us a guideline, and narrows six billion down to twenty thousand. It is our duty to find the one of those twenty thousand who is 'true'. Is that acceptable?"

Tamaki nodded happily.

"Will you stop interrupting my work now?"

Tamaki nodded happily.

"Good."

There was blessed silence for ten minutes.

Tamaki tentatively asked, "Then…will you be my true love, Kyouya?"

Kyouya sighed, and set down the pen. He was nearly finished, and would take three minutes before sleeping to do just that. He said, "Very well, Tamaki."

Tamaki beamed. "Then you have to promise that you won't ever have another true love!"

"Very well, Tamaki."

"Then, here, listen: 'I love you, Kyouya'. Now you say it back!"

It was a small sacrifice to a child's game. Kyouya said, "I love you, too, Tamaki."

Tamaki was no longer on the couch, and hurried over to hug him. "So now we're true loves forever!"

"Yes, Tamaki." This was beginning to become annoying.

"Better than all the rest of the sixty-twos?" Tamaki insisted.

"Yes, Tamaki." How could Kyouya end the game?

"And your eight point three, that's done, too?"

"Yes, Tamaki." Kyouya had an idea, but he felt vaguely guilty to even consider it.

"You should be excited, Kyou-"

Kyouya turned his head and kissed Tamaki, and pulled away quickly.

Tamaki put a hand over his lips. "What did you do that for?"

Kyouya said, "That is the sort of thing that true loves do, Tamaki. It's time to end this game and be serious. You will marry a very nice, pretty girl who is able to control you, and I will marry a very polite, studious girl who does not mind having a shrewd bastard for a husband. That will be that."

Tamaki threatened wetness. "But…besides them, we can be true loves, can't we?"

Kyouya said shortly, "We will be adults then. You will outgrow such a game."

"You promised, Kyouya!" Tamaki clung to his friend and begged, "At least until I outgrow it!"

Kyouya wished that he had the ability to deny Tamaki. "Fine. Until you outgrow me, we will be true loves."

"Hooray!" Tamaki leaned in and kissed Kyouya.

Kyouya very calmly asked, "Why did you do that?"

Tamaki winked. "You stole my first kiss, so I stole yours."

Kyouya said, "You can't steal my first kiss by giving me my second. I gave you my first kiss while stealing yours."

"What? Wait! That's not fair!" Tamaki whined.

Kyouya sighed. Why did every conversation with Tamaki leave one of them emotionally off balance?