A/N: Hello, this is my first fanfiction posted on this site and I hope you'll enjoy it, but before starting there are a few things that you need to know:

This fanfiction will take place around one year after the Future Arc, which means that it will have the "Good Future". The Arcobaleno curse was broken, friends and relatives didn't die, Fran never joined the Varia, the Milleifiore never existed, etc. You can use your intuition to assume the rest of the facts, since I won't remember them all.

It will be a collection of one-shots, and each of the chapters will be divided in three parts. The first part shows how the characters switched places with their future selves, the second part shows what happened in the future while they are switched, and the third part shows what happened in the past, while still switched. The order of the parts might change, depending of the chapter but I'll make sure that it doesn't get confusing.

Lastly, there will be pairings and I will specify them in the beginning of each chapter, in case you don't like certain pairing and want to skip the chapter. As for the rating, it can from K to T.

For this chapter, there will be no pairings unless you squint a lot.

I guess that's it, I apologize for the long A/N (The next ones will be a lot shorter, I promise) and hope you have fun.

It was just one more day in Namimori. People would go on with their lives, shopping, driving, studying, whatever was most appropriate for them. Lovers exchanged kisses and caresses while sitting on the hard park benches. Best friends would walk together, side by side looking at the shops and wondering that things they could buy. Mothers and children would go out of their houses to play, or merely enjoy the good weather. It was a calm day, after all.

Except in the Sawada household.

"Waaaaah!"

There was a loud clank, followed by a thud and another shriek.

Coincidentally, the day happened to be October 13th. And since Reborn had arrived in Japan, this day stopped being just a common day to become an eventful birthday. Because of that, everyone had gathered to celebrate. Reborn himself had sent invites to the whole Family and friends. Everyone was there; even Hibari ―who had made a sacrifice for Reborn's sake and was currently sitting on the roof, at least not so close to the crowd― accompanied by the Disciplinary Committee.

"Tsuna-san! Are you alright?" Haru exclaimed, followed by Kyoko, Gokudera and the rest of the Guardians, sans Lambo who was being chased by I-Pin at the moment.

"Owowow. It hurts! Really…" Tsuna whined, rubbing his head and then taking Haru's hand to stand up, ignoring Gokudera's protests.

"What happened anyway, Tenth?" Gokudera asked, worry already flooding his gleamy green eyes.

Tsuna looked around just to find that almost everyone was staring at him. Some even exchanged whispers between themselves. He then felt a blush creeping up his cheeks and immediately tried to hide it with his hair. He was glad that Hibari wasn't there at least, or else things would have been even weirder.

"Ah…I-It's nothing much. I just fell from the ladder while trying to help with the decorations."

How great, it seems like he was still Dame-Tsuna after all. Some people then shrugged the matter off and resumed to what they were doing, be it talking or helping prepare the party. However, all of them were interrupted by the arrival of the birthday man, Reborn.

"Ciaossu!"

He smiled as everyone turned their attention to him. He was wearing a white suit, special for the occasion and no hat, carrying Leon on his shoulder instead.

"How do I look, Tsuna?" He made his way through the crowd until he was close enough to his student.

"Ah…"

Tsuna was caught off guard by the question. If he said something like 'normal', Reborn would probably hit him, and if he said something like 'beautiful', Reborn would hit him anyway. It would be even worse if he said something bad, so…

"Time is up." Reborn didn't hesitate on kicking Tsuna in the head, adding to the pain of the fall from earlier.

"Oww, Reborn! Was that really necessary?!"

"Mafia bosses can't be slow in their decisions."

"But I'm not going to be a…never mind, there's no point in arguing, especially since it's your birthday."

He watched coyly as Reborn nodded and started dragging him to the middle of the crowd.

"Let's go Tsuna, I have to make my initial speech."

Tsuna opened his mouth to complain but was interrupted by a very familiar laugh.

"Gyahahahaha! You can't catch Lambo-san! I-Pin snail!"

And as Tsuna predicted, Lambo ran towards him and Reborn, followed by I-Pin, but what Tsuna didn't predict was what happened next.

Lambo tripped, making the 10-years bazooka come out of his hair, but instead of falling on himself it fell right on Reborn. Tsuna shrieked in horror as pink smoke surrounded the baby Arcobaleno. The last time that it happened, everyone had had to go through something horrible. He was wary about it, yet now he knew that they had changed things and none of that would happen again. The Arcobaleno curse had been broken in the future, after all.

In the future, things looked almost the same, except for the less amount of people and the fact that the party was being held at the Vongola base in Namimori instead. At least Tsuna's house was safe from the potential fights that could occur, especially because this time Hibari couldn't escape as much. Although he was still willing to stay for Reborn, there were no roofs where he could isolate himself, so he had to stay in one of the corners of the room, being constantly distracted by Kusakabe, who wanted to avoid trouble as much as possible.

Everything had been normal so far, chatter and drinks weren't lacking. Fun seemed to be everywhere, in a more adult atmosphere than ten years ago. But suddenly a burst of pink smoke startled at least a few guests, Tsuna included.

"Tsuna, something happened?" Yamamoto interrupted his chat with Gokudera to look at the surprised Tsuna.

"Impossible. It can't be."

"What is it, Tenth?" Gokudera also turned his attention to his boss, box already in hands.

"Look there, Hayato." He pointed to the place where the smoke had appeared; now that it had dissipated they could see the form of a well known baby.

"Ciaossu."

"Hiiiiiiiiiiie!"

Tsuna screeched but immediately covered his mouth with both hands. He really thought that he had lost that habit years ago, but apparently he'd still do that in extreme occasions, like that one. He hit his own head mentally, though. His voice really sounded weird when he screamed like that. He was a grown man, frankly.

"I thought you had improved, Dame-Tsuna, but I can't waste my time with you right now. Where is the stupid cow?"

"You mean Lambo?"

"He is right there, Reborn-san." Gokudera replied before Tsuna could, pointing to where the Thunder Guardian was.

Without waiting a single second, Reborn rushed there as fast as he could.

"Hey, stupid cow."

"Yes? Ah, it's Rebo—"

He couldn't finish his sentence because Reborn had already hit his head with the hammer-shaped Leon.

"Wh-what did I do?" The older Lambo asked, already teary-eyed.

"Your younger self should learn to take better care of that bazooka of his."

"But it wasn't—"

Another hit and Reborn walked away, leaving a crying Lambo behind. Now he just needed to wait a few minutes and he could go back to…

"Baby!"

Another familiar voice caught his attention. As it seemed, Hibari had finally noticed that the Reborn from the past was there. His eyes glowed in a strange sort of way as if he was seeing an idol, as he walked in the baby's direction, pushing everyone out of his way.

"Ciaossu, Hibari. It's been a while since I last saw you like that. How have you been?"

"Ah…I've been—"

A "poof" was heard; interrupting Hibari and making Reborn disappear again, bringing him back to his time. Five minutes were up.

Meanwhile, in the past everyone was still startled about the sudden smoke and the possible disappearance of Reborn. Tsuna and the Guardians were going to seek for him but as they were about to do so, a voice of an apparently unknown man filled the room, coming from inside the smoke.

"I actually had planned on spending this day sleeping or drinking, but since idiot Tsuna insisted so much I decided to stay…" He looked around before resuming speaking "…except not here. Was it the stupid cow's doing?"

"Hiiiiiie, impossible! Is that….adult Reborn?!"

It seemed like whatever year it was, Tsuna would always be Tsuna after all. Reborn on the other side promptly ignored the boy, scanning the room with narrow eyes, searching for his target. And then, in a swift moment he had caught Lambo by the hair. The child started squirming and crying

"Who are yooouuuu, man who dresses just like Rebooorn? Lambo-san didn't do anything wroong! Release me! Tsunaaaaa, heeelp!"

"Shut up." Reborn simply said, and threw Lambo through the window without hesitating, leaving everyone wide-eyed.

"Hey, Reborn! You're not the same size as him anymore did you know?" Tsuna was brave enough to interfere.

"And? You have no right to talk, Dame-Tsuna. Become as strong as your older self and then go speak to me."

Tsuna was about to reply to that but his Guardians and the girls didn't let him. It would just be a waste of time.

They didn't even notice when Hibari jumped through the broken window.

"What is going on? Do you want to be bitten to death?" He said, without addressing someone specific.

"H-Hibari-san!"

"Hey, what are you doing here? Get the fuck out!" Gokudera growled, ready to light up his dynamites.

"Calm down, Gokudera! He hasn't done anything yet." Yamamoto tried to calm Gokudera without much success.

"Boss…do you need help with that?" Chrome asked shyly.

"Yes, Sawada! We can help you TO THE EXTREME!" Ryohei practically screamed, but Kyoko intervened, pulling him by the arm and saying things along the lines of "Onii-chan, don't go causing more confusion."

A loud sigh was what it took for everyone to stop talking. Reborn then made his way to Hibari and caught his wrist, without the slightest hint of worry in his expression.

"Kyouya, ten years or not this is still my birthday. I understand your hate for crowds, but don't go destroying anything at least for today." And then he stood closer, whispering in Hibari's ear in a friendly way "If I wasn't going to return to the future I would let you beat them all up tomorrow as much as you wanted to. They are in need of that."

Hibari just blinked in half amusement, half confusion. He wasn't even sure of who that man was. Well, after the birthday comment it had became obvious, but still.

"…Are you…the baby?"

"Not a baby anymore as you can see. And that was thanks to all of you." He admitted sincerely and then turned to Tsuna.

"Five minutes are almost gone. So…get stronger. All of you, get stronger. Especially you, Tsuna." He released Hibari and then smiled to the brown haired boy who one day would become such a good boss for the Family.

Tsuna couldn't even say anything about that, because in the blink of an eye the older Reborn was already gone, being replaced by the baby again.

"Where's the stupid cow?" Was the first thing that they heard. Apparently Reborn hadn't had his complete revenge yet.

"Your future self threw him through the window…" Tsuna mumbled, not believing at how his tutor could act so normally in that kind of situation.

"I see. That's wise of me. Well, let's get going, I still have a speech to make and after that, you'll train so much that your arms and legs will crumble."

Tsuna sighed and complained all the way. That was going to be a long day…And he hadn't even wished Reborn a happy birthday. But there was always time.


And that was the first chapter. Thank you for reading. Please leave a review so I can know what you think? Even if you didn't like it, concrit is always welcome!