Hello! :D
This fluffy one shot was requested by a mutual on Tumblr, and I decided to post it here as well. Please enjoy! ^-^
By the way, Natsu's birth date and age are both unkown, this is fiction.
Also, I do not own Fairy Tail.

"Man, that mission was quite boring." Natsu complained before letting out a yawn. He looked down at his partner. The Exceed was happily swinging his tail, walking energetically, and eating the fish the Mage bought for him, much obliged. He raised an eyebrow.
"Weren't you too exhausted from the heat you couldn't move?" With his mouth full, Happy pointed at the rest of the fish in his hand. Natsu sighed. Seriously, how is fish supposed to refresh someone? He didn't even bother asking, because he knew the answer would be "Don't underestimate the power of fish!" or "I'm too focused on eating, I forgot the heat."

They walked towards the guild, ignoring the glances and whispers. Everybody knew a pink-haired young man with Fairy Tail's insignia on his shoulder would be no other than the mighty E.N.D. Even though he has only shown kindness towards good-hearted humans, he could still see disgust and fear in some people's eyes. The fact that they looked down on him angered him. He would punch them in the face if he could, but the Council ordered him to not cause trouble. It's not like he cares about those fools' orders or rules, but after Zeref was set free from his curse, they were going to execute him. Fortunately, councilmen with the highest authority were friends of Fairy Tail, and knew about the brothers' story, they accepted to let the man live normally with his little brother as long as they didn't hurt anybody. They were in a sensitive position, so he's been holding back as much as he could.

They finally reached their destination and Natsu opened the guild's gate -which was unusually closed- and got in. "We're ba- Huh?" He blinked at the sight of the guild hall decorated in different shades of red, his favorite color, his guildmates gathered together, staring at him with grins on their faces, and what seemed like a chocolate cake with strawberries at the top behind them.
"Happy birthday, Natsu!"

"HUH?!" His eyes widened. "What is that supposed to mean?! Even I don't remember my own birthday and have never celebrated it because of that reason, how did you guys-" He felt two warm arms wrapping around his chest and recognized his brother's scent. He understood that the former Black Mage was behind all of this, he totally forgot about him being part of Fairy Tail now.
"You were born on the 21st of June, the first day of summer." Zeref said. One of his hands moved up to pet the pinkette's hair.
'The first day of summer, huh?" Natsu smiled
"Yes, Summer, the meaning of your name." He confirmed. "Happy birthday, Natsu."
The demon pulled away in order to turn around and hug his brother. "Thanks, Zeref-nii." He whispered, he then faced his friends and thanked them with a huge grin, leaving the poor man to deal with Happy's "Why didn't you tell me it was his birthday?" nagging. Heck, even the Greatest Mage of History was powerless facing the blue cat's complains, now that he became familiar with him, that is.

"Hey, Natsu..." Lucy walked in his direction, along with Gray and Erza, holding a dozen of papers in her arms. "I've just paid my rent, and have spent the whole day preparing for the surprise, so I didn't have enough time or money to buy you a decent gift, not that anyone had, we were too busy, but I wanted to give you something..." Natsu sighed. She knew that he wasn't expecting any presents from her, or anyone else, because he valued his family, wether It was his guild or his brother, the most and nothing else mattered to him more... Except for food, of course. Food always wins. Food is above all.
"It's okay, Luce." He reassured her with a smile on his face. "You don't really have to-"
"All I had is this." She interrupted him, handing the papers to him. "I've been writing this for a while now, so I thought you'd love to read it.. It's a romance-based comedy, please read it later, I wanted you to be the first to get to do it." She gave him an innocent smile, trying to cover her embarrassment, getting a glare from Levy across the room, probably because she didn't get to read her work before him, and suspicious yet excited looks from Mira, being the NaLu shipper she is.

Natsu was delighted, he wasn't fond of books, but he loved Lucy and everything about her, so he really enjoyed her stories, though he was too shy to admit it, or rather, too scared, because he thought she only considered him as a friend, which was totally wrong. The Demon was too focused on reading the summary that he didn't notice the Celestial Mage blushing slightly. The short novel that she has been working on reassembled their own story in a way. She thought it'd be a great hint she'd give him without having to confess, hoping he'd be smart enough to understand it. Yes, even Natsu could be smart sometimes, well… Rarely. She wanted to let it out of her chest but still couldn't directly tell him how she felt, so she was hoping she was lucky enough to get on his intelligent side.
"They lllllike each other!" The Exceed whispered, loud enough for the older Dragneel to hear. "They should just date already!"
"Well, that'd take some time." The man commented, chuckling at the sight of his brother staring at the page with interest and the blonde's cheeks becoming red. "Natsu's quite an idiot, after all."

"Well, she did participate in baking the cake, isn't that the best present ever? I mean look at this piece of art!" The Seventh Guild Master said, pointing at the mentioned masterpiece with sparkles in her eyes, making Natsu almost facepalm, but he wouldn't, if he made fun of her or criticized her obsession, she'd kill him on the spot. Ah, Erza and her love for cake... Assuming she was fighting the urge to devour it, would she leave enough for the guild members to eat at least?
"Though, there isn't enough room for four hundred candles, so we only put twenty in there, though you're only twenty physically so that should be alright." The Devil Slayer teased, getting a punch from the Demon in return.
"Are you saying I'm old, Ice Princess?" Natsu yelled furiously, feeling highly offended.
"No, I'm just saying that you're four hundred and twenty years old." Gray answered sarcastically. "Have you also forgotten your age, Flame-Brain?"
"Actually, since he's been frozen in time like you in Tenroujima, that makes him four hundred and twenty seven." Zeref corrected, which angered his little brother even more.
"Whose side are you on?" He asked, giving him a death glare.
The black-haired Mage wrapped his arm around the Etherious' shoulder and gave him a faint smile. "Come on, we're just teasing you. Now, how about sitting there and letting us sing Happy Birthday?"
"Hell no. That'd be weird. Besides…" He pulled his brother and whispered in his ear. "A certain someone is too impatient to start eating the cake. If we make her wait any longer she'd probably have a heart attack."
Zeref secretly looked at the Requip Wizard and chuckled. "You're totally right."
Natsu moved towards the cake and stared at the candles for a while then blew them at once after mumbling something, as if making a wish, followed by his comrades' cheers. He then looked towards a knife beside him and reached for it, before feeling a hand grabbing his.
"Why don't you make a little speech for us first? I mean we prepared all of this for you and everything." The Ice Mage said with a grin.
"Not my thing." He answered calmly.
"C'mon, don't be greedy!"
Natsu sighed. "Fine..." He cleared his throat as his friends' eyes were all on him."I… I wanted to thank you, guys for… Celebrating my twentieth… I mean four hundred and seventh birthday. I'm blessed to have you with me, you're all such… Sweet, kind-hearted and adorable friends." They all blinked at these words. It wasn't like Natsu at all. They stared at him with confusion as he took the knife in his hand again and started cutting the cake. He rose his head and smirked at their expressions.
"Don't go believing that you idiots, I was being ironic. You're a bunch of weak, worthless bastards… But it's okay, I still love you— Oww!" He felt a kick in his back that would almost send him flying. He turned around to face an angry Erza.
"WHO ARE YOU CALLING WEAK WORTHLESS BASTARDS— Oh, cake!" Her face brightened as Natsu gave her a plate with a piece of cake in it. Normally he would get the first piece considering it's his birthday but... It's alright as long as it could save his life.

Few moments later, the guild members were eating, drinking, and having a peaceful time, except for Natsu, probably because his dear best friend was getting under his skin.
"Gray, for God's sake, stop making fun of my age! I really don't want my birthday party to turn into a crime scene." He said slightly irritated.
"Oh? So you'd E.N.D. my life, eh?" The Devil Slayer replied, then laughed at his own joke.
"I don't remember giving you the permission to use my name for puns." Natsu protested.
"You can say that my puns are… Gonna be the E.N.D. of you."
"Seriously?" The Demon rolled his eyes.
"Okay I'll stop. By the way, what did you wish for?"
"Huh?" Natsu blinked.
"Before you blew the candles, you wished for something, didn't you? What was it? Getting a hot chick for the first time in your life, or any chicks at all?" He teased, getting a punch for the second time this night.
"I'm not a pervert like you! Geez!" He yelled.
"What do you mean 'like you'? I don't need these things, I have Juvia."
"You still look pervert to me, by the way, where are your clothes?"
Gray looked down and noticed that he was in his boxers. Maybe the Etherious had a point.
"Nah seriously, did you wish for Lucy to love you back or something?" He whispered, making Natsu blush.
"I-I have no idea what you're talking about… P-Plus I don't wish for these things anyway…"
"Then what?"
"I just…" He sighed and glanced at Tartarus' insignia on his skin, for some reason he didn't want to remove it. "I just want people to accept my brother, I want him to live like a normal human without being feared and rejected."
"Well, I doubt he would…" Gray replied coldly, Natsu looked down.
"Listen, I know that you hate him because your family was indirectly killed by him, and you've got the right to, but—"
"No." The Ice Wizard interrupted him. "I don't hate him. Of course I didn't get over it, but after getting to know him I came to accept him. I... Understand his reasons, I guess. After all, if he didn't go through this, that ass of yours would never be here." Natsu smiled.
"Well, I'm glad you've forgiven me at least." Hearing a voice behind them made them jump off their seats.
"Okay, that was creepy! Seriously, if you spy on people you probably wouldn't get to live normally." Gray commented, pointing at the former Black Mage.
"Sorry about that. I was just passing by and heard you two talking about me." He apologized calmly. "By the way Natsu, what you said about wishing a peaceful life for me was adorable, come here you cutie." He pulled his little brother and hugged him tightly, too tightly, almost breaking his bones.
"Zeref-nii, I.. Can't.. Breathe…" The Wizard pulled away.

"Aww, what a heartwarming scene!" The Guild Master said, walking towards them while eating her seventh cake piece.
"It is indeed." Lucy confirmed.
"Aye!"
"Yeah, it was heartwarming." Natsu looked at his the girls and Exceed. "Until he started choking me to death."
"I'm your big brother, I've got the right to kill you if it includes hugs." He argued, gently stroking the Demon's hair.
"About that…I may have accepted you as a person, but not as Natsu's brother." Gray commented. Zeref looked at him confused.
"Huh? Why?"
"Not until you do it."
"It?"
"He's right, we can't confirm you're really brothers as long as you didn't do it." Happy approved. Erza and Lucy nodded in agreement.
The man looked at his sibling, seeking an explanation. "What's it?".
"The Dragneel Smile, I guess." Natsu answered.
"The… Dragneel Smile?"
"You know, that cute smile we've got in our genes. You've never been really happy so you couldn't smile from the bottom of your heart, but now you are, right?" He pinched his brother's cheeks, "Come on, consider it as a birthday gift for me!"
"Fine, fine, I got it!" He pushed the pinkette's hands, feeling embarrassed.

He then looked at the Mages and took a deep breath before a toothy smile drew on his lips, reaching his eyes, probably because being with his brother and, almost, living like any other human being made him truly happy, for at least once in four hundred years.
"I've been wanting to see this for a long time." Natsu said, wrapping his arms around his brother.
"Does that make me a confirmed Dragneel now?"
"Yes it does." Erza answered. Wiping few tears from her eyes.
"Yeah. I thought you didn't really look alike for brothers, but you do have the same smile." Gray nodded.
"Don't we look alike at all?" The man pouted.
"Well, you do have the same angry face…" Happy whispered. He learned this the hard way, he swore never to mess up with these two again.
"Your hair colors and eye shapes are different, though." Lucy added.
"Oh, speaking of hair colors… Zeref, is Natsu's pink hair a side effect of his resurrection or something?" The Ice Mage asked.
"What are you talking about? He was born with it." The former Black Mage answered.
Gray looked towards Natsu. "That was… Your natural hair color?"
"Got a problem with that?" The Demon yelled.
"Well, don't know, it's... Pink."
"Okay, that's it."

Natsu growled, hitting Gray with his Fire Dragon's Fist, which leaded to a fight between them. And it wasn't long before Erza joined in… And as usual, it turned into a brawl between mostly all the guild members.
"They never learn… Why did I even join this guild?" Lucy sighed, she managed to avoid getting dragged in this time.
"They're as energetic as usual." Zeref chuckled, observing the guild members' fight. "But it should be fine as long as Natsu doesn't use his curses or Etherious form."
"I can't even think about it… His Dragon Slaying magic alone is enough to destroy this building in a second…" She commented.
"He has grown into a troublemaker, well, he seems to be having fun… That's just how he shows love towards his friends, right? He used to be so attached to me when we were kids, but now he's got other people he can depend on. You've all taken good care of him, and I'm really grateful."
"That's also thanks to you, you've granted him this second life." She smiled at the way he was gazing at his brother. "You really love Natsu don't you?"
"The same goes to you." He replied, staring at her.
"Huh?" The Celestial Mage's cheeks became as red as Erza's hair.. "Wh-What are you talking about?"
"Nothing." He looked back at the Etherious and smiled. That tiny little fluffball has become a strong and handsome man now. He surely has grown so much.

"I'm glad my sacrifices haven't gone to waste." He thought as tears started forming in his eyes.

I hope you liked it! Please give me your opinion, I accept all kind of reviews as long as they're respectful!