Hello there :) This is my first take on an OP fic. I hope you guys like this one! :D I wrote this just because it's 101010 today. :)

Just Because

-Greentulip-

A girl in her late teens wearing an oversized jean shorts that reached halfway past her knees, a red vest shirt and a red beaded necklace, sat on one of the rails of the Moby Dick, staring lazily out in the open sea.

She was idly, yet gently fingering the red beads that hung loosely around her neck. Nobody was up yet considering it was still midnight. Well, she wasn't complaining. It was times like these where she could feel him the most.

It has been almost two years since the fight at Marineford. And although she has a crew to get back to, she decided to visit uncle Whitebeard for a few weeks before heading back to Sabaody where she would reunite with her beloved nakama.

She was so mentally stricken when her brother died in her arms that day. She rampaged so much in Amazon Lily that she almost felt sorry for Jimbei when she thought back to what happened. She felt a small smile graze her lips as she thought about it. Hey, she said almost, didn't she?

She was so lost in her thoughts that she almost didn't feel the warmth of a blanket placed on her shoulders as a young man with blonde hair in his mid-twenties stood beside her.

After a while no one spoke a word. Both were just enjoying the gentle rocking of the boat and the soft caress of the wind as it gave them a cool breeze. So, he was slightly taken aback when she spoke softly.

"Ten times."

"Huh?" He dumbly asked. 'Great. Way to go, Marco.'

"Ten times" she repeated with a giggle.

"Ten times, what?" He asked, thoroughly confused.

"Ace would usually have a narcoleptic fit ten times a day."

"Oh."

After that, nobody spoke for a while, Luffy being lost in her thoughts while Marco was simply enjoying the moment at her side.

"Ten days."

"What was that?" He asked.

"Ten days."

"What about it?"

"Ten days is the longest fight Ace and I had." She smiled sadly.

"Oh? What was it about?" He inquired.

"Well, it was about our third sibling and Ace actually." She laughed half-heartedly.

"You had another sibling?" he inquired thoughtfully. Ace never actually told him about that.

"Oh, I guess Ace didn't tell you. Well, it's probably because you didn't ask." She said thoughtfully.

Marco sweat dropped a bit. "Who is it then?"

"Sabo..." She said barely above a whisper but he still managed to hear her.

"Sabo? The author?" Marco asked, wracking his brains to impress the brunette.

"Yeah. He always said he was going to sea and write down his adventures, too bad for him though, I hate reading. Bleh." She stuck her tongue out while scrunching her face towards the sea.

Marco chuckled lightly before crossing his arms and leaning against the railing.

"You never actually told me how you ended up fighting with Ace."

"Ahhhh. Well, you see..."

Flashback

The grey terminal was like an inferno. Burning trash, burning flesh, burning chemicals were filling her little lungs as her eyes watered.

"Where's the treasure that you brats hid?"

Luffy stuck her tongue out as she was trashing viciously while dangling from the scruff of her shirt.

"Why you little!" Bluejam was about to strike Luffy on the cheek when

"Let her go, you stupid punks!" Ace ran towards Luffy when the Bluejam pirates were knocked out suddenly.

"Wow, Ace! How did you do that?" Luffy asked, her eyes sparkling with amazement.

"I don't know. Let's talk about this later. We need to go!" Ace said hurriedly as they were running.

"Of course you run away." Bluejam taunted Ace.

"What did you say?" Ace asked as he turned around.

"You heard me. I said you're a coward, turning tail just like that." Bluejam scoffed.

"Why you-" Ace was interrupted when he felt a tugging on his shirt.

"Ace! Let's go! Forget about him! Look! There's Dadan!" Luffy relentlessly tugged on Ace's shirt.

Ace stood rooted to the spot and removed Luffy's grip from his shirt and ran towards Bluejam.

"Ace!" Luffy was about to follow him when Dadan picked her up and gave her to Magura and Dogura.

"Go back and treat her wounds." Dadan ordered them and trudged off to follow Ace.

"That brat's a chip off the old block when it comes down to it." Dadan murmured.

End of flashback

"That idiot didn't come back for almost two weeks. And when he did, he was limping while carrying a half-dead Dadan on his back."

"I told him how worried I was that I even skipped meals and thought he was dead and all." Luffy's face was getting as red as a tomato as she thought about it.

"He blew off on me, saying that 'you don't make people dead when they're not.' He screamed at me. I was so mad."

"So, I built a house and stayed there for ten whole days, refusing to speak to Ace. I eventually missed Sabo though. So, when I saw Dogura running to the house, I asked him what's wrong and then he told me that Sabo was killed by the World Nobles."

"It rained so hard that night you know. I ran to the cliff and just lay down there, face down. I cried my eyes out."

"The next day, I was so sick. My head pounded so badly. But, I heard him. Ace was running around, shouting for my name, and he saw me. He had tears in his eyes and a letter clutched in his hand. I never knew what it was though."

Flashback

"Luffy!" Ace ran around frantically.

"LUFFY!" Ace shouted with all his might.

"MONKEY D. LUFFY!" He tried once more.

Ace saw a lump on the dirt. If he wasn't observant enough, he would have passed right by it, but then he saw it. Luffy's most prized boshi.

"Luffy! What the hell! What are you doing here? Did you stay out here all night?" Ace fired question after question at Luffy while feeling her forehead.

"You idiot! You're burning!"

Luffy ignored the comment and said hoarsely "Ace..."

"What is it?" He asked softly.

"Don't die like Sabo." Luffy said with tears streaking down her eyes.

"You baka. Do you think I'd die and leave a wimp like you to fend for herself?"

"Promise me." Luffy said more firmly.

"Fine. I'll never die, no matter what." Ace said as he carried Luffy back to Dadan's house.

"And just so you know, I'm not a wimp anymore! My punch is like a pistol now." She said while demonstrating it to him, but failed miserably because she caught the flu.

End of flashback.

Marco chuckled lightly.

"Hey! Don't laugh. It's not funny. My punch IS like a pistol." She pouted.

"What happened to Sabo, then? You said he died?"

"As it turns out, he was with my dad all along. I was with Iva-chan and Inazuma-san and we were going to see my dad when I bumped into him. It was funny, actually. I screamed at him for three hours straight. Well, that was a bad idea since my dad was sleeping at the time. So that was the story of how I ended up cleaning the revolutionaries' base." She smiled a bright smile and waved it offhandedly.

"Hmmm, that was interesting." Marco started while staring ahead of him. 'Here's your chance Marco! Tell her how you feel!'

"Luffy?" Marco started.

"Hmmmm?" She said while closing her eyes and bathing under the light of the moon.

Marco turned his head to look at her when his breath hitched, his heart jumped, and his tongue got caught in his throat. He quickly spun his head to look at the most interesting thing in the world right now. His feet.

"Marco? What was it?" Luffy asked while staring at him curiously.

"I-uh-you-dance-summit-pirate." Marco stuttered. 'Ooooh, 'cos Marco you sound real cool right now.'

They both stayed silent. Luffy was drawing idly on the rails with her finger while Marco was trying to be coherent again.

"You..." Marco never got to finish his sentence when he felt additional weight on his shoulder and soft snores.

"Will you go to the pirate summit ball with me?" He whispered quietly.

Marco sighed and carried Luffy back to her cabin.

Well, since before while watching One Piece, Ace told Luffy to meet him in the Pirate Summit. At first, I thought it was an event where all pirates from the New World gathered. But, then I realized it was just Ace's way of saying 'at the top'. So, here.

Tell me if you guys want a second chapter, okay? If not, I can leave this as it is. :)

Love it? Hate it? Review.

-Greentulip