Based off a fanart I've seen floating around on Google; I thought the idea was cute, so here we are. Crossposted from my AO3 account, TokitoTaishirou

If anyone asked him later, Luffy would say that it wasn't his fault.

It was his brothers'.

After all, they were the ones who left their precious hats lying around the house. Luffy, on the other hand, was somehow the responsible one. He kept his Hat with him at all times, never letting it get dusty or potentially lost. No, he was the good caretaker, thank you very much. Because, well, Luffy would never forgive himself if anything happened to Shanks' hat. That Hat meant the world to Luffy; he'd never do anything so, so…what would the word even be? Distrustful? Dishonorable? Sacrilegious? No, dishonorable worked best. He'd never do anything to lose Shanks' trust in him. Luffy knew how to take good care of other's prized possessions.

His brothers, on the other hand, were apparently content with leaving their hats sitting anywhere and everywhere in the house. How they could keep track of them, even, Luffy didn't know. It was really unlikely, but in the off chance that Luffy left Hat somewhere other than on his person or with a trusted friend he was sure he'd probably end up losing it on accident. That was how Luffy lost a lot of things, actually. But, then again, Ace and Sabo were somehow the more reliable, responsible siblings. Well, Sabo definitely was, at least. Ace had his moments, though.

Standing in the living room with his arms crossed over his chest, Luffy looked down at the two hats before him in disappointment. He wasn't quite sure where Ace and Sabo might have wandered off to, or if they'd gone ahead and left somewhere with their friends. But somehow or another, their two hats had been left on the coffee table, left to wonder where their owners had gone off to. It was sad, really, to think that these precious hats had been abandoned as they were. Tilting his head to the side, Luffy thought. Thought about what the best way to teach his brothers a lesson would be.

After all, Luffy was their little brother. He was allowed to get on their nerves and needle them from time to time, especially when he wanted to show them that he was right and they were wrong. After a childhood of receiving noogies, losing fights, and in one particular instance receiving a wet willie (thanks for that, by the way Ace), he felt it was only right to take his brotherly revenge where he could.

And it wasn't like Sabo and Ace were stupid or anything. After looking around for a bit, they'd no doubt figure out that Luffy had something to do with the hats' disappearance. If anything, he was going to be holding on to them for safekeeping. What if while they were gone, some burglar broke in and stole Ace and Sabo's hats? They'd be lying out in the open for the whole world to see. It would be better if they were hidden away, for their own safety, at least.

Plus, it would be funny to see how long it took them to notice their hats were hidden in Luffy's room.

Laughing to himself gleefully, Luffy grabbed both hats and ran to his room, lightly bouncing off the walls as he went. As he entered the room, Luffy took a moment to ponder where best to hide the hats. For obvious reasons, he couldn't just shove them into a draw somewhere or they'd get squished. He just wanted to play a prank on his brothers, not actually damage the hats.

He wasn't an asshole.

Pursing his lips in thought, he lifted his hands that held one hat each as he slowly turned in a circle. He had a feeling Sabo wouldn't be too happy with him if Luffy stuck the top hat in his closet like he'd originally been planning. Sabo could get fussy that way. Then again, Ace wouldn't like it if his hat ended up buried under dirty laundry, which was the next hiding place…

As he turned around, Luffy caught a glimpse of himself holding his brothers' hats in the mirror over his dresser. In the mirror he stood with a serious expression, holding Sabo's hat in his left hand and Ace's in his right, with Hat being perched rightfully on his own head. Luffy tilted his head, lifting up first one hat and then the other. It could have been because they were older, but Ace and Sabo's hats seemed to be bigger than Luffy's somehow. The thought brought a pout to his lips before he grinned wide. It figured that his brothers would be bigger; after all, they were his big brothers. It was kind of irritating in a pride kind of way, but Luffy didn't mind so much. He loved his brothers, and there wasn't any denying that they were, at the very least, better fighters than him. They seemed to be better in general, which only made sense; they were older, they had more experience than Luffy had at the moment.

It wouldn't last, though. Luffy was determined to beat his brothers one day; until then, they were worthy rivals, goals to be reached, and his dear older brothers.

Older brothers with huge heads, though, Luffy had to point out again. It almost felt like he could probably fit his own Hat in one of theirs.

…

How would that look, even? Would one of them dwarf his own in comparison? Would his Hat prove to be the most superior Hat in existence and be able to balance both hats on his head? Would it be something else? Luffy would readily admit that he wasn't that great at imagining consequences, but he couldn't even picture what it would look like. One thing was for certain, though, and that was the fact that if he was able to wear all three hats at once then Luffy would somehow be vastly superior to his brothers in every way. That was the law of hats, so he couldn't be wrong.

After a quick moment of contemplation Luffy decided to put Ace's hat on first by virtue of it being orange. With Sabo's black top hat on last, it would make the others look like some kind of super hat with three brims. Seeing absolutely nothing wrong with this solution, Luffy then proceeded to place Sabo's hat on last, carefully tilting all three so that they would be at the angles that would most allow for stability as well as field of vision. What did it matter that he would have three hats on if nobody could see him wearing three obviously different ones?

Frowning thoughtfully, Luffy adjusted the hats even more. This way anyone would be able to see Ace's hat ornaments as well as the red rim to Luffy's own Hat poking through at the sides. For all anyone knew, the middle one could just be some random cowboy hat that Luffy found. With the two smiley/frowny faces showing, no one would be able to say that the middle hat wasn't Ace's. Sabo's was shifted so that it faced forward towards the mirror with the goggles clearly visible as well.

It was almost like his brothers were there with him, Luffy thought happily. They tended to hang out with their own friends and go off on their own adventures, which was fine. Luffy did the same with his friends. Still, it was nice to have that reminder that even when they were apart they were together. Who knew where Ace and Sabo were at the moment. They were both planning their own trips and were supposed to leave soon, if they hadn't already left yet. For just this moment, though, he could practically feel his brothers there with him. He closed his eyes and laughed quietly to himself at the thought.

Sha-shink!

Luffy opened his eyes, blinking curiously at the strange, yet familiar, sound.

"Luffy? What are you doing?"

Flushing furiously, Luffy looked towards the open door of his bedroom. Oh yeah, he forgot to close that… He should have had more time before his brothers came home again. Standing framed in the doorway, grinning furiously down at his phone, Sabo waited for some kind of answer from his younger brother. Luffy could practically hear the pleased, teasing smile in his voice.

Freezing up slightly, Luffy took a moment to realize that he'd had a plan, before this. He'd had a plan to mess with his brothers. He was supposed to have taught them a lesson about keeping their treasured objects safe. Unfortunately, it looked like he'd gotten sidetracked and caught at possibly the most embarrassing moment. What even was Sabo doing home right now?

"Sabo!" Luffy whined, hurriedly whipping the other two hats off his head. Why did it feel like he'd been caught doing something else? "Wha-what are you doing here?! I thought you'd left already for some camping trip with your friends."

Sabo clicked away at his phone, his smile never once dimming an inch. This didn't bode well for Luffy. "I was going to leave soon, when I realized my hat was missing. I thought you might have something to do with it."

Well, he wasn't wrong. Caught, Luffy could do the only thing he could think of. Try to throw his brother off the trail. He shifted his eyes away and pursed his lips, hurriedly hiding Sabo's hat behind his back. Maybe he hadn't noticed yet. Sabo seemed more interested in what was going on on his phone right now, so it was a possibility at least. "I-I don't know nothing about your hat…" If it worked, Luffy could maybe still pull off his prank.

Sabo looked up finally and quirked his eyebrow. "Luffy. I literally have a photo of you here with both my hat and Ace's. You can't lie to me."

Luffy looked wildly towards his brother—his brother who was supposed to be the good, the nice one out of the three of them. "You have a picture of that?" There was no way in any universe or galaxy or whatever that that would ever be a good sign for Luffy. His brother perking up at the reminder of the picture didn't help to calm him down, either.

"Of course!" Sabo said cheerfully, turning his phone over to show said picture off. It was of Luffy clutching onto both of his older brothers' hats while smiling goofily at his bedroom mirror. "It's my wallpaper now." Why?

Okay, somehow this whole 'prank' thing turned out really, really bad for Luffy. This wasn't the way things were supposed to go. Sabo and Ace were supposed to learn a lesson, not embarrass him to death! Luffy could only imagine what everyone would say when Sabo showed off his new favorite photo. He was just embarrassing that way. God, if Gramps found out about it…

"Sabo, please don't show that to anyone!" Luffy begged, leaping forward to try and wrap himself around his brother, maybe steal the phone to delete the picture, whatever worked. He even turned on the puppy dog eyes; Sabo was very rarely able to resist Luffy's puppy dog eyes.

Unfortunately, this looked like one of those rare instances. Sabo held his phone out away from his body, keeping Luffy at arm's length as he did so. If anything, he looked amused at Luffy's plight. "No, I think I'll keep it. Maybe show Ace just how cute our baby brother is."

Luffy recoiled back in horror. "I am not cute!" Normally he didn't mind being called the baby brother, since, well, it was kind of true. Now, though, it felt like just another nail in his coffin, so to speak. At least, Luffy thought that was how the saying went. Sabo either didn't hear him or was ignoring him as he walked down the hallway towards the living room. Even more infuriating, it seemed like he was humming to himself.

"Hey Ace, check out this photo I took!"

"What? No, Sabo, come back!" Luffy took off after him, trying to head him off. Hell only knew what would happen when Ace saw that picture. Knowing Ace, he'd take the picture and run with it, probably showing everybody in town before Sabo even had a chance to. And he knew just what his brothers would say, too.

Luffy was not cute! He was going to be a great man someday, and great men were not cute!

He just reached the living room after Sabo who was still keeping his phone away from Luffy. Ace stood on the other side of the room looking down at the coffee table in annoyed confusion. He had his hands on his hips and a frown pulling his lips down, perplexed. So far it didn't look like he'd noticed the struggle going on between Sabo and Luffy yet. He hadn't even looked up from the table yet, his brow furrowed in confusion.

"Okay, who took my hat?"

Sabo smiled wickedly. "I can show you~!" Ace looked over at his struggling brothers, staring at them in bewilderment.

"Do I even want to know?"

"Ace! Don't look at Sabo's phone!" Luffy shouted at him. Somehow, Ace seemed to take that as a dare since he walked straight over to Sabo and took the phone from his waiting hand. He stared at the photo for a moment before bursting into laughter. Luffy could feel his doom upon him.

"Oh, this is great, Sabo! Luffy, you look so-"

"Don't you dare say cute!" Luffy protested, finally giving up on trying to take the phone back. He crossed his arms, standing with his back partially to his stupid brothers. This was just the worst.

"Hey, Sabo, you got to send me this picture!"

"Sure thing."

No, correction. That was the worst. "Oh, come on! You don't really need that picture, do you?" Pouting hadn't worked on Sabo, but maybe Ace was in a more forgiving mood.

"Of course I do," Ace nodded seriously. Luffy wasn't fooled, though; he could see a slight smile starting to peek out. "As your older brother, it is my duty to have every available piece of embarrassing moments that you have at my disposal. Sabo and I were thinking of starting an album, actually."

Luffy stared at his demon older brothers, aghast. "That's not—why would you—you guys are stupid!"

Luffy didn't need to take this kind of embarrassment from them. And besides, he had to meet up with his friends. Without looking back he marched towards the front door with hunched shoulders. Ace and Sabo were both going to be gone for a few weeks; he'd have the whole house to himself, and it would be awesome. Okay, so he'd invite his friends over every available minute he could, but still; it would be awesome. No stupid older brothers to deal with…

"Hey, Luffy, give me back my hat!"

And then Ace and Sabo died tragically, leaving Luffy alone to think back on the good memories together…
Lol, nope. This is an Everyone Lives modern AU, so yeah; no dying.
At. All.
(Looking at you, Ace…)
Hope you liked it!