Author's notes: Out of all my stories, this is my favorite, hehe.

Born For You
by ilYamaTsuna7227li

Chapter 1

February, in a desolate underground laboratory…

"The subject is stabilizing ma'am!" One scientist called out to the black-haired lead who was looking through the piles of report. They were currently in the deepest level of the Vongola laboratory, it was filled with different sorts of machines and boxes and papers littered the room. In the middle of it all was a glass container containing the purpose of their experiments.

A human zygote.

"That's good! We'll have the subject ready before the tenth heir will be born!" The woman with long black-hair stated as she tucked a strand of her hair behind her ear. "Have you imprinted its purpose."

"Imprinting now…" There were sounds of beeping as flashes of light came from the glass container.

"But who will we inject the zygote to?" One of the scientists asked her companion.

"Me." The lead scientist said with authority causing everyone to turn to her in astonishment.

"But ma'am-!"

"Tsuyoshi will be glad to hear that I'm pregnant. He doesn't have to know that the child is merely an experiment created for the tenth boss." She stated in a firm tone and she looked at her stomach patting it.

"But this child, after injecting it to you, will be born only after 2 months. Wouldn't he notice that?" The other reasoned.

"Tsuyoshi doesn't know anything about woman pregnancy. Besides a woman's stomach gets noticeably bloated during the last 2 months. It'll be fine." She assured them.

"But Yamamoto-san, the labor is going to cost you your life!" Another argued but the female Yamamoto held up her hand.

"I know that. But I'm willing to take the risk." She turned to look at the forming zygote in the glass container. "I created him therefore he's my responsibility. I will carry the burden of nurturing him in my own body."

The scientists in the room exchanged uneasy looks but the head scientist just smiled at them.

"I'll be fine."

April 24, Yamamoto household…

"ARGH!" Long black hair was spread messily across the white pillow as a pale hand clutched tightly onto the person beside her.

"Hang in there, he's almost out." Tsuyoshi told his wife anxiously. The woman took comfort in the voice knowing that in a few seconds it'll all be over and she just had to hang on.

"Takeshi…" She and her husband had long thought of a name for the young lad after finding out that it was a boy she was siring. Finding out that he and his wife was going to have a child, a boy nonetheless, made Tsuyoshi the happiest father in the world.

"He's almost out!" A friend and colleague of the female Yamamoto was doing the delivery. She came as fast as she could once she heard that the woman wouldn't be able to make it to the hospital. Her hands were shaking in anticipation, wondering what she would be seeing once their 'experiment' was born.

"AH!" Mrs. Yamamoto screamed at the pain as her body arched and finally she felt something being taken from inside her. She fell back upon the futon with a soft plop and a tired sigh as her body relaxed slowly after the labor.

Big amber eyes blinked as they saw the light of day for the first time. Unlike other infants, Takeshi Yamamoto did not cry once he was finally out of the warm womb that was his mother's.

The Yamamoto's friend shivered as she looked down on their completed experiment. He looked like a normal baby, with wide amber eyes, a small tuft of black hair on his head and a flushed and chubby face… but somehow she knew better.

"G-Give him… L-Let me see him…" The laborer looked up and she saw the pale lips of the female Yamamoto forming words. She felt worry roll down her spine as she gave the small boy to the woman. Beside her, was her oblivious husband who was happy at the fact their child was born safely.

"Takeshi…" The female Yamamoto cooed at the baby who waved his fat fist into the air. "My child, my precious son…"

"Takeshi…" Tsuyoshi said as he patted the soft head of the baby boy while smiling proudly. He got up to get some water for his wife and left.

The female Yamamoto didn't know how long this happiness between her small family would last. Already, she could feel the drain and the side effects of giving birth to Takeshi in her system. But for now, she'll try to hold them back so as to make her husband happy. She would try to last as long as she can, because even she wanted to stay alive and watch her son grow.

"Takeshi…" She whispered hoarsely to her son when Tsuyoshi went to get her a glass of water. The only person left behind was her colleague who helped with the labor. "Takeshi, promise me, that whatever happens in the future, please fight for the things that are important to you… Hold on to them and make sure to never let go."

In reply to her words, the small baby Yamamoto yawned and snuggled into her warmth.

A week later, Yamamoto Tsuyoshi's wife died in her sleep.

Five years later…

It was cold, so cold and so dark…

He was abandoned, an outcast, no one wanted him, no one loved him… He was of importance to no one, now that his parents were gone.

It was a tragedy no one foresaw. But somehow, he had felt it that night as he was being tucked into bed by his mother.

He didn't know why those big scary men wearing ski masks and black overalls came after them. After all, they were an average family, living in a two-story average house. Surely nothing big can come out of stealing from an average family?

But his parents were panicked at the sound of the door in the first floor being broken down. For some reason, Nana and Iemitsu didn't even try calling the police as they grabbed him and hid their only son somewhere.

However, hiding him had cost them their lives, because once they had successfully hidden the youngest Sawada, those men came in and killed them, right in front of their son's eyes.

Not knowing, that another Sawada was still alive, the men had exited after performing their task, leaving the young brunet crying in the closet as his parents bled out on the carpet.

He had escaped that house on the same night and had been wondering the streets, crying for help on the alleys as it rained harshly while people stared at his dirty form in contempt and disgust. They thought he was just another street child.

"Mama! Papa!" Young Sawada Tsunayoshi, who was barely five-years-old, uttered the only words he could say in his broken state. He hiccupped and sniffled as adults ignored his cries while others threw him a look of pity.

Small legs could only carry him so far and before long, the young Sawada found himself by the river crying hoarsely as he collapsed into the wet pavement. The rain continued to pour down on him harshly. "M-Mama-!" The young brunet cried as he looked around. But no one was there. "P-Papa!"

He didn't know how long he had been crying there. All he knew was that he felt so cold and so numb that his body was shaking not only from his sobs but also from the coldness he felt from the rain.

That's when he suddenly heard footsteps coming his way.

Teary brown eyes blinked and looked up as a child about his age, but taller than him, stop in front of him. The other had black hair and blank amber eyes and was soaked to the skin the same as him.

Tsuna sniffled as he looked up at the kid who was surveying him blankly. "H-Hello-?"

Amber eyes blinked. And was it just Tsuna or was light suddenly gathering in those mysterious orbs?

"Your name?" The taller boy asked as he leaned down to look at Tsuna. He tilted his head. "What is your name?"

The brunet opened his mouth. "T-Tsuna…" He sniffled as he said it while tears ran down his face. "Sawada Tsunayoshi…"

Amber eyes widened and for a moment Tsuna was blinded by the light that gathered in those eyes. "Tsuna…" The other repeated in awe. And to the brunet's shock, the other grinned at him. "Tsuna!" Before Tsuna knew it, small arms suddenly enveloped him into a warm hug. "It's nice to meet you Tsuna!"

"H-Ha-?" Tsuna said but then he was pulled upwards with the other still hugging him.

"I've been wanting to meet you for a long time!" The young boy stated still grinning. "I've finally met you! The reason for my existence!"

"E-EH?"

W-What?

Takeshi was a strange kid. Tsuyoshi Yamamoto had realized that as his only son grew up. He didn't know if it was because he was a bad parent or maybe it was the effect of growing up without a mother, but still Tsuyoshi felt that somehow he had failed both his wife and his son.

The young sushi chef sighed as he sliced the tuna he was preparing for a party tomorrow. His amber eyes, so much like his son's, looked over the silent dark-haired boy staring out of the window into the heavy rain.

Takeshi was silent, he was obedient, but he was also strangely empty and seemed to lack emotion. He hadn't cried even once during his infancy and as he was growing up, no other kids would approach him. Sure, whenever Tsuyoshi would tell his son to go out and play, the other would oblige but more than not, he would find his son playing alone rather than with other kids who shied away from the strange boy.

"Takeshi, what do you like to have for dinner?" Tsuyoshi asked for the sake of conversation. Takeshi Yamamoto turned to his father.

"Anything is fine." He said and Tsuyoshi inwardly frowned.

"Even if it's all vegetables?" The older Yamamoto asked and Takeshi just nodded. The sushi chef sighed again.

Don't kids usually hate vegetables? Putting down his knife, Tsuyoshi picked up a hand towel to wipe his hands. "Look Takeshi, there's something I've been meaning to tell you-"

SCREECH!

Tsuyoshi looked up, startled by the sound of the chair dragging across the floor. Takeshi never made irritating noises like that whether accidentally or on purpose. "Takeshi?"

Said boy was standing up, looking outside the window with a startled expression as though he sensed something beyond the heavy rain. The older Yamamoto rushed immediately to his son's side. "Takeshi what's wrong?"

"I-I'm going out…" He said in a blank tone which sent shivers down Tsuyoshi's back. "I'll be back soon…"

And without further ado, the youngest Yamamoto ran outside into the pouring rain.

"Takeshi!"

It was the longest ten minutes of Tsuyoshi's life. He had pacing around the room in worry, waiting for his son to come back and inwardly swearing that if the younger boy wasn't back in the next minute, he would go look for him. But before he could grab his coat and an umbrella, the door to their restaurant opened and a soaking wet Takeshi entered.

"Takeshi!" Tsuyoshi cried out in relief as he hugged his son despite how wet he was. "I was so worried! What were you thinking rushing out like that-!"

However, the old Yamamoto was cut off from ranting when a whimper suddenly reached his ears. Startled, the other let go of Takeshi and looked down at his son, wondering why the other made such a noise.

But it wasn't Yamamoto who made the sound…

"Hello, who do we have here…?" Tsuyoshi stated in puzzlement when he saw a small boy with brown hair and eyes hiding behind Takeshi, looking equally wet.

The young brunet whimpered and Tsuyoshi's eyes widened when Takeshi suddenly held out his arms in front of the other protectively. The sushi chef was shocked to see determination color the amber eyes as he looked at his father.

"Don't hurt Tsuna." Takeshi said firmly and for some reason, Tsuyoshi felt pride swell in his heart.

"Maa… Takeshi, you know I'll never do that." Tsuyoshi stated as he patted the wet black hair and somehow the other relaxed. Tsuyoshi didn't know what happened, but somehow he got the feeling that this was a different Takeshi from ten minutes ago. It was like a switch had been turned on inside his son. "So his name is Tsuna huh? What are you doing here Tsuna-kun? Where are your parents?"

At the mention of his parents, young Tsunayoshi's eyes filled with tears and he began to cry again. Realizing he made the younger boy cry, Tsuyoshi was about to apologize but to his great surprise, Takeshi turned his back on him and hugged the younger boy.

"Maa, Tsuna! If you have nowhere to stay you can stay with us! Right Papa?" Takeshi said with a wide grin and Tsuyoshi felt this heart stop. Takeshi called him 'Papa'! Takeshi smiled!

"Y-Yes! Of course! You can stay here as long as you like Tsuna-kun!" Tsuyoshi patted the brown-haired kid and the young Sawada looked up hopefully.

"R-Really?" He said with a small and hopeful voice. Tsuyoshi's eyes softened.

"Really." Tsuyoshi said and at that word, Tsuna's teary face broke into a wide smile, thus making Takeshi smile as well.

That night, to celebrated the new edition to their family, Tsuyoshi cooked up the tuna fish he had been saving for the party and served it to his two sons.

It was the night that Tsuyoshi experienced many firsts with his only son Takeshi. The first time Takeshi smiled, the first time Takeshi laughed, the first time Takeshi called him 'papa', and the first time Takeshi said that his favorite food was tuna.

It was a happy day and Tsuyoshi was willing to keep Tsuna in the family if it meant his beloved Takeshi would be happy.

Because in retrospect, it was like Takeshi was born to meet Tsuna. And if it meant his son would continued smiling like this, then Tsuyoshi didn't mind it at all.

Nine years later…

"Tsuna!" It had been exactly nine years and four months since Tsuna had been taken in by the Yamamoto household and truth to be told, the brunet hardly remembered much of what happened back then.

"Yamamoto…" Tsuna said with a smile as he watched his 'brother' rush down the stairs and towards him. It was early morning and the two of them were getting ready for school. "Good morning, had a good sleep?"

"Of course!" Yamamoto laughed as he placed an arm around the brunet when he was near enough. "And you? Did you have nightmares again?"

Tsuna shook his head. "I'm fine. I don't think I dreamed at all." The other laughed and pressed a kiss to the younger one's forehead. The brunet let him, already used to the affections of the other.

"Good. That means you can focus on your lessons today!" Yamamoto said and the brunet frowned towards the other.

Yamamoto Takeshi, the only son of Yamamoto Tsuyoshi was of course as expected, a very popular student of Namimori Middle School. Aside from the fact that the other was tall and handsome, his upbeat personality and cheerful disposition naturally drew others to him.

Of course, popularity had always a bad side to it.

Yamamoto was also well-known for being very fond of his adopted brother Sawada Tsunayoshi. As they grew up, Yamamoto would never agree to go anywhere or play with anyone unless Tsuna was there with him. This, of course, warranted unwanted hatred for the young brunet but since Yamamoto was with him practically wherever he went, the brunet would always be saved before things got worse.

A few years before…

"Hey! What do you think you're doing to Tsuna!" An angry Yamamoto said towards a group of bullies. The dark-haired boy was just off to buy Tsuna some ice cream but when he got back he was met with the sight of the brunet being kicked on the ground.

The young brunet ran crying behind Yamamoto, as amber eyes glared seriously at the bullies before him. It was the scariest sight Tsuna had ever seen.

Of course, after defeating the bullies, Yamamoto had realized how much he scared the brunet so then and there he swore…

"I'm sorry Tsuna. I swear I won't get angry again, I don't want to make you scared of me." The young dark-haired said to the crying brunet in front of him. "But I want to protect you Tsuna. I live to protect Tsuna and I'll do whatever it takes to make you happy."

Of course, sappy lines like these had always been spewing out of Yamamoto's mouth ever since they were kids and Tsuna could never understand why those words were only ever directed at him.

Seriously, Yamamoto could pick up girls with that sort of line.

Speaking of cheesy lines, just last week…

"Yamamoto-sama please go out with me!" A girl said as she looked up hopefully at the baseball idol. Of course, during confession times like this, Tsuna was always dragged out by the baseball idol.

"Ahaha, gomen but I'm not interested!" Yamamoto stated cheerfully and the girl glared at Tsuna before turning to Yamamoto.

"B-But why?" She sniffled pitifully.

"Because the person I only need is Tsuna." Yamamoto said with a smile and if Tsuna hadn't heard that line over a hundred times he would've choked. "I exist only for Tsuna."

The girl gapped at the idol before she turned around and ran like her butt was on fire. The brunet sighed, knowing that this would stir up the rumors that he and Yamamoto were going out.

Tsuna couldn't blame the girls for thinking that way, especially what with the lines Yamamoto said regardless of whether they were in a public place or not.

"Tsuna let's go on a date tomorrow!" Yamamoto said as they walked towards school. Again, if Tsuna wasn't hearing this at least thrice a week, he would've gapped like a fish and gone very red. So instead of doing that, he looked calmly at his brother who continued to grin at him.

"Yamamoto, I told you already what a date means…" Tsuna sighed at his best friend.

Yamamoto pouted but then he cheered up and said, "I know… Oh and can you please call me Takeshi instead of Yamamoto?"

Tsuna smiled at the other but shook his head. "You know why I don't call you Takeshi especially in public." The brunet hinted, subtly pointing out girls who were glaring his way.

"I know but I still don't like it." Yamamoto stated as he placed his arms behind his head.

The brunet sighed. The reason why he never called Yamamoto his first name was because if he did, the female and male population already hated and despised him for being so close with the idol, and if he was anymore closer… well, he doubted even Yamamoto could stop them.

But of course, the young Yamamoto never complained about the fact that Tsuna never called him by his first name. He sometimes requested Tsuna to call him Takeshi but after that he keeps quiet about it. He valued Tsuna's safety more than any sentimental care.

Which was strange considering how young Yamamoto was to be all mature about Tsuna's safety.

"Hey Tsuna." A warm hand on his alerted the brunet back to his surroundings.

"E-Eh?" And then Tsuna flushed when he saw his and Yamamoto's intertwined hands and almost immediately he retracted. "What is it?" Calm down, calm down! It's just Yamamoto… He told himself. He really didn't like it when Yamamoto caught him off guard like that. He could practically feel his skin tingle from the contact.

"Well, you never answered my question." The black-haired pointed out, not at all perturbed by his best friend's actions. "Can we go on a date or not?"

"Yamamoto…" Tsuna whispered as girls sent out 'I-hate-you' signals as they passed. "Why do you want to go on a date so badly? If you want to go on dates, why don't you get a girlfriend?" The girls who heard Tsuna nodded their heads enthusiastically and Tsuna retracted that thought when he saw that.

Never mind, please don't get a girlfriend. Tsuna wanted to say but the sharp nails of the girls made it hard to take back his words.

Yamamoto raised a skeptical eyebrow at Tsuna, as though hoping he was kidding. "Why should I get a girlfriend when I have you?"

Tsuna's heart skipped but then he vehemently told himself to calm down. This was Yamamoto, the brunet had known him for spouting cheesy lines since they were five! No need to get so self-conscious!

I've been wanting to meet you for a long time! I've finally met you! The reason for my existence!

Tsuna blushed. Even after several years he could still remember the first words Yamamoto said to him after he introduced himself.

"Tsuna…" Yamamoto said in a slightly whining tone as he placed his hands in his pockets. How could he look so manly and be so childish at the same time? –Tsuna thought in envy. "Can we please please go out on a date tomorrow?"

Seeing amber eyes looking at him hopefully, all the brunet could do was nod and then sigh in exasperation.

"Fine." He said and a brilliant smile lit up on the athlete's face.

Tsuna never really understood how a simple yes from him can make someone like Yamamoto so happy. The other was so simple-minded, the things he wanted weren't money, riches, or more possessions like every other normal teen. The black-haired teen was simply satisfied with whatever he had. And as to his favorite gifts for Christmas and birthdays…?

"Oh yeah, you're birthday is coming up…" Tsuna remembered and his brown eyes met amber ones as he asked, "What do you want for this year?"

And as Tsuna expected, the energetic sportsman just grinned and said, "Anything that Tsuna will give me."

Because really, Tsuna could've given him a used battery or a battered sock with no pair and the lovable idiot would've loved it anyway.

"Hey Yamamoto!" A co-baseball player greeted the Namimori ace as he entered the clubroom with his usual grin. The other responded in a cheerful manner as he put his bag down and opened his locker.

"Is Dame-Tsuna out there again?" One new player sneered and the other players tensed, thinking how stupid it was for this fresh recruit to insult Tsuna in front of Yamamoto. Sure doing it when the baseball idol wasn't around was cool and all… but when Yamamoto was around… well…

It's better to just hold your tongue. Or better yet, cut it off.

Said baseball idol paused in the action of chucking, his already taken off shirt in his locker. The normally grinning athlete's face was reduced to a blank one: careful, listening…

…slightly murderous.

"Man, that guy is such a loser!" The newbie continued, and the other people in the room wished he would say less for a change. "Always hanging around you like that, Yamamoto. Honestly, he should get a life right?"

"Actually." The tone was razor sharp and many shivered and backed away, some tried to sneak out of the door. If the newbie had a brain cell or two, he would've figured out that this was the sign to stop talking. "I was the one who asked Tsuna to come and watch me during baseball practice. You shouldn't call him a loser, without knowing the full story. Haha."

The laugh was horrible. It was a warning: sharp, quick, and lightly murderous. But maybe the guy was just too dense to understand anything. Or otherwise, really stupid.

Oh how the baseball members wished to get out of there now. They didn't want to be questioned by the coach as to how the new member got beaten up by an angry Yamamoto- which was rare since Yamamoto was rarely angry unless…

… it concerned a certain brunet.

"Oh? But either way he's still a lo-!" CLANG!

The newbie froze as a fist appeared out of nowhere and punched the locker he was facing at, denting it impressively. Most of the guys in the clubroom winced but the newbie gulped, paled, and felt his legs shake in fear.

Looks like he finally realized he overstepped an invisible boundary.

"Oops." Yamamoto stated with a grin as he retracted his hand which strangely enough didn't seem hurt but was only slightly red. "Looks like I missed." He laughed and then his amber eyes looked at the newbie with warning. "I was aiming for something softer and stupider."

The guy gulped, and abandoning all pretense of looking tough, slid down to the floor in fear. "Y-Ya-Ya…"

"Aw, what's wrong? You look scared." Yamamoto extended a hand still smiling. "Maa, maa… Don't worry I won't do anything to hurt you. Tsuna doesn't like it when I hurt people." The newbie could practically hear the hidden message behind those words: The person you called a loser, saved you, idiot.

But instead of feeling grateful, the guy felt even more annoyed.

"What's wrong with you?" He practically screamed in Yamamoto's face. The members of the baseball club, jumped in fear but Yamamoto was eerily calm. "You could've killed me with that you know! You'd have gotten suspended or… or… expelled!"

But Yamamoto still didn't react to those feeble words of threat.

"Why is Dame-Tsuna so important to you anyway?" The guy continued screaming. "What the hell do you see in him? Why is he so important to you? He's just a no-good-!"

BAM!

The newbie's eyes widened as Yamamoto's fist made another loud sound when he punched it centimeter's from the newbie's face.

"Tsuna is the reason for my existence." Yamamoto grinned and the guy choked.

"S-Stop with that nonsense-!" BAM!

"Tsuna…" Yamamoto phrased the sentence slower and his eyes glinted in all seriousness to show that he wasn't fooling around. "…is the reason for my existence."

And with that fist shaking somewhere near his head and the dangerous eyes looking at him, the newbie found himself nodding enthusiastically in fear.

"Yamamoto?" A voice suddenly called from outside as someone knocked on the door.

The reaction was immediate, the baseball idol retracted his fist, straightened up, and jogged to open the door with a true and happy smile painted on his face.

"Tsuna!" The idol chirped happily as he saw the brunet when he opened the door. "What's up? Something wrong?"

"Nothing, I was just coming by to say that I was going to get something to eat. Would you like some too?" Tsuna asked and the idol grinned.

"Sure! I'll go with you!" Yamamoto said happily and Tsuna nodded but then added with hesitance.

"But Yamamoto I'd prefer it if you go with me while wearing your shirt. I don't want anyone fainting from…" Unable to word what he was thinking, the brunet just emphasized the athlete's half-naked state.

As though just realizing this, Yamamoto scratched the back of his head sheepishly and laughed. "Oops." He went back into the clubroom, grabbed a shirt, put it on, and ran back out. "I'll be back later guys!" He said before closing the door behind him and leaving with Tsuna.

All the while, the newbie sat there stunned at how fast the athlete's mood changed while the club members went about their usual business, slightly used to it.

"Hm, Yamamoto really does believe that Dame-Tsuna is his reason for existence huh."

"He should just use lines like that to pick-up girls instead."

"What? So you don't believe him?"

"Hard to believe something like that."

The guys in the clubroom continued to talk about the recent happenings as they all changed their clothes and filed out of the clubroom one by one for practice. They didn't notice the newbie looking down at the floor spitefully.

"I'll get you one day, Yamamoto Takeshi." He said as he tried to stand up. "I'll definitely get my revenge." He took out his phone from his pocket and smirked when the background of his phone lit up.

It was a symbol of a yakuza.

Author's Note: Edit of Chapter one.