Author's Note: Hello, wonderful readers! This is a new story that I've wanted to write for a long time and I'm super excited about it XD For those who are following my other story, Brothers Under the Moon, have no fear! I will be finishing that one before I start going crazy with this one.

I was just so excited that I wanted to post the first chapter!

Anyway, please enjoy and let me know what you think!

It was a beautiful day on Dawn Island. The sun was shining, and the animals were all basking in the warmth. Luffy giggled as he dodged the incoming tide, sticking his tongue out at the stupid sea water that thought it could catch him. The small thirteen-year old continued to run along the water's edge, loving how the sand felt between his bare toes.

When Luffy drew near to the end of the beach, he laughed and flopped down onto his back, squinting up at the bright sun. Today was his "fun" day since Ace was off with Makino working on his manners and stuff. He had the whole day to do whatever he wanted!

As he lay there, a crab ran into his hand, causing Luffy to smile and gently pick up the thing by its shell, careful of the pincers.

"Ne, Crabby, wanna play with me?" Of course, the crab said nothing. Luffy set his new friend back on the sand next to him and sat up, shaking the sand out of his raven hair. After a few minutes of basking, the boy stood up and shoved his straw hat down low onto his head. It was about time to go find dinner. Wouldn't Ace be proud!

After taking only a few steps, the boy's attention was drawn to something washing up on his playground. Curious, Luffy padded over to get a better look. There, bobbing in the waves, was a strange… fruit? It looked kind of like an apple but with strange yellow spots all over it. Maybe it had gone bad or something?

Well, one thing Luffy knew for sure, was that the best way to test if a fruit had gone bad, was to take a small "test" bite. The boy smiled softly, remembering how Sabo had scolded him the last time he had "tested" a fruit that way. Luffy didn't understand why he had been so angry! How do you know if something has gone bad if you don't taste it? For a moment, a shadow passed over the boy's face.

'Sabo… I miss him so much.' The boy bit his lip to try and stop it from quivering. It had been years since his big brother's death and he still cried when he thought about it. Shaking his head violently, Luffy slapped his cheeks hard. Like Ace always said, they had to move on.

Returning his attention to the weird fruit, Luffy gingerly grabbed it from the water, careful not to get too close, and skipped backward out of the tide's reach. Bringing the fruit close to his face, the boy sniffed it and turned it around in his hands. It didn't smell rotten and seemed okay…

Still, Luffy was reminded of when he had accidently gained his rubber abilities. Hadn't Shanks said something about… exploding if you ate more than one? Was this a devil fruit? It looks a little too normal to be one. The boy huffed, passing the fruit from one hand to the other.

Well… if it was a devil fruit, wouldn't it have sunk to the bottom of the ocean like he always did? So, if it floats… Luffy smiled, 'It must be safe!' Deeming the strange fruit good to eat, the straw-hat wearing child took a small bite, and immediately gagged. Luffy's eyes widened when he recognized the putrid taste. Desperate to get the piece out of his mouth, the boy used his fingers to try and grab it before he swallowed, only succeeding in pushing the bite farther back, until he swallowed instinctively.

For a moment, Luffy was frozen, trying to process what he had just done. Then, frantically, the child ran his hands up and down his body, checking for swelling or signs he would be blown into teeny tiny pieces. When he found nothing, the small boy breathed a sigh of relief. It must have been just a stupid tasting fruit.

Then the pain came.

Luffy screamed as white, hot pain tore through his body. It was unlike anything he had ever experienced. Grabbing at his head, the boy collapsed to his knees, tears steaming down his face. Bringing his hands up to where he could see them, Luffy's eyes widened in fear. The boy's small quivering hands were completely covered in fresh blood.

His ears then began to pulse, as if someone was trying to tear them off. Writhing on the beach, Luffy started to crawl towards the forest. If…if he could just get to Ace… everything would be fine, he always knew what to do!

'B-big brother… p-p-please… help me…'

Ace was worried. The sun was going down, and Luffy was no where to be seen. He had searched everywhere around their tree house and had found nothing. Normally, on days when he had lessons with Makino, Lu would stick around and play with nearby beetles or something, but not today. The freckled boy's eyes widened in realization.

'The beach! He wanted to go to the beach!' Earlier that day, Ace recalled Luffy bouncing excitedly in place and exclaiming just how much fun he was going to have in the sand. Not a second passed before Ace started sprinting through the forest, praying he would find Luffy taking a nap or something.

When he finally broke through the tree line, Ace looked around frantically, trying to spot his baby brother's straw hat.

'There!' Down on the other side of the beach, he could see Luffy's hat and the small body it was attached to, laying in the sand. Unmoving. Surrounded by a puddle of blood.

Ace's shoes struggled to gain traction on the loose sand as he ran towards his brother, throwing himself down next to the motionless form.

"LU! Oh God, Lu! W-what happened!? Please, talk to me!" Ace moved Luffy gently and cradled the limp form in his arms. The freckled boy gasped as he got a better look at his brother's face, which was nearly completely covered in now dried blood. Ace's breathing got quicker as he realized the blood was still coming from Luffy's ears… or at least where they were supposed to be.

Had-had someone c-cut off… Ace's grey eyes burned at the insinuation. Swallowing hard, the teen looked around for a weapon or-or something and his eyes landed on a fruit, with a single bite in it, laying innocently next to Luffy's prone form. 'Is that…'

Holding in his panic, Ace scooped up his brother, making sure to grab the straw hat and the suspicious fruit, and began to run. He had to get Luffy to Dadan. Holding the limp body close, Ace felt tears start to well up in his eyes. Lu was all he had left. If he died…

'I-I wouldn't have a reason to live anymore!' So, engrossed in his thoughts, the sixteen-year old nearly tripped but caught himself just in time, his grip tightening on his baby brother's wheezing body. Luffy would be fine, he had to be.

Hours later, Ace paced back and forth, waiting for Dadan or one of her bandits to come out of the room they were treating Luffy in. He kept thinking back to the incident with the bear, in which he was put into the familiar situation of waiting… and his baby brother had nearly died. Ace stopped pacing and let his back slide down the wall of the house, burying his face in his hands.

Luffy was precious to him. He had shown Ace a love that he had never known. Lu accepted him, heritage and all. It was gut wrenching to think that he might never see that bright smile again.

At that moment, the door opened and Magra beckoned to him. Ace immediately rushed to Luffy's side.

"Is-is he gonna make it?"

Dadan took a drag from her cigarette, "Well, he's a stubborn one. His breathing stabilized during the treatment, but I'm honestly not qualified for this kind of thing." Ace settled himself down on the floor and brushed a hand through Luffy's unruly hair.

"Did he…do what I think he did?" Dadan motioned for Magra to bring over something swaddled in cloth.

"Yeah… it would appear the brat ate a second devil fruit." The orange-haired woman unwrapped the cloth to reveal the fruit, which looked the same as when Ace had first seen it.

"Why-why isn't he dead then? I thought if you ate a second fruit, you would-" the teen asked, but stopped short as he felt something in Luffy's hair. Grabbing a lantern from the table, Ace allowed the light to illuminate what he was feeling, and his jaw dropped.

There hidden amongst the raven locks, right where his ear should be, was a-a…

Moving himself to straddle the unconscious boy, Ace used both hands and pulled the new ears away from the hair, so he could see them better. Dadan leaned in for a closer look.

"Are those… cat ears?" Ace gently thumbed over the new appendages, watching with wide eyes as they twitched under his touch.

"What… kind of fruit did he eat?"

A week later, Ace sat with his back up against a tree, watching Luffy stalk a beetle on all fours. His little brother had recovered amazingly well for someone who had nearly bled out on the beach. Thanks to the devil fruit he had eaten, the thirteen-year old now sported fluffy, black cat ears on his head and, something Ace had not noticed until after his brother had gotten out of bed, a long tail that swayed behind him. His baby brother had turned into a cat... sort of.

The teen sighed, "Lu, how do you feel today?" The small boy gave him a bright smile, giving up on the chase for a moment.

"I feel great! It's super weird, Ace, everything is so… loud now!" Apparently, along with the appendages, Luffy's senses had gotten an upgrade. Wonderful.

Ace beckoned to the boy, "Come here, Lu. Let me check you over." The kid bounded over and plopped himself in the teen's lap, looking up expectantly. He had healed very well, and very quickly. Which was surprising considering the circumstances. Ace decided to blame it on Luffy's ridiculous luck.

"Do your ears hurt at all?" The boy shook his head.

"Not really, they're a bit sore I guess. It's taking some getting used to though." Ace cracked a smile as the kid reached up and played with them a little bit. Unlike cats he had seen around town, Luffy's ears were not directly on top of his head. Instead, they sprouted exactly where his… well, old ears had been, drooping naturally, with bits of white fluff showing underneath.

Luffy said he liked them that way since his hat could rest on top of them without it hurting. But, in Ace's mind, that also made them more difficult to hide.

Moving on, the teen had Luffy turn around, so he could lift his shirt and check over his lower back, where the tail now resided. With all the blood gone, it was easy to see the insertion point along with how swollen it was. It had no doubt hurt. Horribly.

"What about the tail, Lu? Does your back still hurt?"

His brother shook his head, "It's a lot better than it was." Ace breathed a sigh of relief. It was so good to know that Luffy was going to be okay. He smirked and wrapped his arms around the now squirming child.

"You are so DAMN lucky, Lu. Anyone else would have died, ya know." The boy squealed as his brother began to tickle him relentlessly.

"Noooo…" Luffy laughed, "S-stop it!" Ace tickled him a little while longer before releasing him and leaning back against the tree with a content sigh. The small boy snuggled against Ace's chest, wrapping his tail around the teen's calf.

"You…you don't think I'm weird now?" Ace raised an eyebrow before pulling the kid in for a hug.

"No, Lu, I don't think you're weird." Ace ruffled his brother's hair and scratched at the ears, "If anything, this change just makes you more adorable."

Luffy pouted a little at that and readjusted himself in the elder's lap before taking his hat off and curling in around it.

"I love you, Ace. Always, forever, no matter what." The teen smiled fondly at the now dozing cat-boy in his arms.

"I love you too, Lu."

Luffy's mouth opened wide in shock as he attempted to process what he was being told.

"W-what?"

Dadan sighed, "Garp's coming back. I informed him of what happened and described the fruit to him and, next thing I know, he says he's coming and taking you with back with him, brat." Beside him, Ace growled.

"What!? He can't do that!" The small boy wrapped his arms around himself to try and stop himself from shaking. He was going to be taken away?

"Calm down, Ace. From what Garp told me, he needs Luffy to stay at a marine facility, so they can figure out why he was able to eat two devil fruits."

"For how long!?" Ace yelled, pulling Luffy in snug to his side. The boy leaned into the elder, grabbing his tail and fiddling with it nervously.

Dadan shrugged, "I don't know. All I know is that he'll be here in about a month and that the brat can't take anything, or anyone, with him."

Luffy was scared. What kind of… facility… was he going to? Did they want to hurt him for being different, like those kids did when he was little? Ace's grip tightened around him.

"SCREW THAT!" The older boy grabbed Luffy's wrist and started running into the forest. Ace didn't stop until they reached their tree house.

Luffy was confused as he watched his brother rummage through their things and start to pack their bags. "A-ace? Are we going somewhere?"

"Yeah, out to sea." The boy's eyes widened at that, his ears twitching a little.

"But… it's not time for you to leave yet."

"I don't care. Sabo would understand." Ace threw him his now packed bag and shouldered his own before kneeling on the wooden planks, placing his calloused hands on Luffy's cheeks.

"I'm not letting you spend the rest of your life as a pin-cushion. We're going to be free." Luffy sniffled and nodded, rushing in to give Ace a quick hug.

His big brother always fixed everything. Ace wrapped his arms around the shuddering cat-boy, "You ready to be a pirate, Lu?"