"Mugiwara, you've been fighting Jii-san really well! How do you do it?" Luffy was sat besides me as I was laying down in the Domain with my own thoughts. I suppose Garp's training has been exhausting, I didn't last two minutes using all that Haki, I think I passed out around twenty-no fifty times! I need to really improve my stamina somehow.

"A lot... it takes a lot out of me to just do it." I responded, sitting up and looking at Luffy, he did appear to be stronger according to my Kenbunshoku Haki, however I want to see if that's the case. "Luffy you've gotten stronger, right? Show me."

Luffy had a cheeky smile and attempted to attack with a Gomu Gomu no Pistol, what was interesting was that he was supposedly stretching his arm less and less the more times he used it. That is similar to the change in the time-skip where he no longer puts his arm behind him to attack. I clearly dodged it, but there was something else which surprised me, the Gomu Gomu no Bazooka. I suppose if I didn't have Kenbunshoku Haki I might have been able to dodge it through ducking or even jumping.

"Damn it! You're too fast!" What's even more interesting is his proficiency in being a rubber man, it's grown significantly during the past few days. It's without a doubt that Luffy has become quite strong in the past few days, he's already gotten down a lot of his common techniques.

"I admit, you've improved a lot. But, you won't be able to catch up to me so easily!" Well, I suppose I'll try training my rubber proficiency meanwhile.

I put my arm backwards, throwing it even to make it stretch... but it didn't. For some reason I wasn't a rubber man. I suppose the devil fruit as eaten by Luffy and belongs to Luffy, because of that only he can use it in the Domain. I see, so this confirms that things aren't shared between us in terms of power and strength. So, my Haki definitely isn't mixed with his... so it truly is just extremely strong.

I suppose this does put a dent in things, after all I won't be able to train gears in the Domain and will have to do it outside in the real world. Well, it's alright I guess, I did make some improvements to the concentration effect so that there's even more Haki on layers.

"Luffy, I'm heading out, I recommend getting a way to get even stronger than you are." I suppose if he can work on the gears himself then it'll be alright. Although this changes a lot, my fighting style will have to focus on Haki primarily now, I can't slack off even slightly.

~~~

"You've improved greatly, Luffy! Truly worth to be a marine!" Garp seemed proud of my increase in strength, with his help the past few days I've managed to improve Kenbunshoku Haki quite a lot with the help of Garp, his attacks made it hard to dodge even if I was using it, not to mention my stamina also improved! Instead of two minutes, it's now up to 2 minutes and 30 seconds! I suppose I may have to develop a style at this point to actually make sure that I get the most out of using Haki.

"I suppose so oldie, but where were you going to take me the other day?" I decided to try and focus on the path of heading towards Ace and Sabo, I've got to get to that part in the story, a lot of events depend on it. We were both currently resting near a fire in the middle of the night, Luffy would always come out to eat the meals and I would talk to Garp. It was the most beneficial method.

"Oh, and whose asking now? Luffy or the other one?" Garp chuckled. Huh, what the hell? Did he figure out that I'm not Luffy, nevertheless did he even figure out that I share a body with Luffy? Damn, I shouldn't have under-estimated a vice-admiral of the navy.

"How did you figure it out?" I gave in, since Garp would probably never shut up if I tried to deny it. It may be an assumption, but I think trying to argue with anyone whose name is 'Monkey D.' is stupid.

"Well, it's clear that Luffy's still in there, I've seen his impatience the past few days and his eating habits. You however, are more well-mannered and polite, you are also very calm!" Well, that's actually kind of my fault, Luffy has been coming out in the recent days and mucks around while I train. Garp had a clear picture of the difference. "Then there's your Haki, if Luffy managed to learn Haki then I think the sun will crash into Earth! Even the red-head wouldn't teach him it. It's incredibly strong as well, I've only seen it once before."

"Before? Where have you seen it before?" If Garp has some information on how I ended up in Luffy's body, then I have to know undoubtedly.

"Oh, where? It's clear as day, when you were born." Luffy's birth? He felt it at Luffy's birth? So is my willpower somehow linked to the reason to why I'm in Luffy's body?

"When Luffy was born...? So that means I was somehow in Luffy's body the same time he was born?" I pondered. So it was clear that I was in Luffy's body before he was even a day old. So that begs the question why I didn't appear until he was seven years old.

"You're misunderstanding! I mean when you were born! It's clear who you are." Does Garp know who I am? It's odd, since he's saying that it was when I was born and not when I was myself. So does this mean that I was born in this world somehow? "You're Luffy's older twin sister, Maris. It was a surprise that there were twins, completely unexpected. You were born with Haki, extremely potent Haki, yet you died shortly after being born."

Sister...? SISTER? I was born as Luffy's twin sister yet died? I admit I'm surprised that I'm a girl, although I knew that my gender wasn't confirmed, so it could've been anything. However, this doesn't necessarily mean that I was a girl beforehand, it could just mean that I was born again as a girl!

This does pose a new theory however, if I was dead yet had such strong Haki, it's possible that my spirit made its way into Luffy and sat there waiting for something. What that was is a mystery.

It was unexpected, but I felt something faint, it was as if I had just gotten a small headache. I closed my eyes in order to try and imagine how the events would've taken place, but it appeared that I was taken aback!

I remembered something!

I was standing in front a mirror, my black hair was all curly, it stretched down to the centre of my spine and was left off there. My eyes were light blue, but the highlight was my skin. It was exceptionally pale and even rough from the look of it, it's clear whoever I was I was involved in something dangerous! However, what lightened the mood was the dress I was wearing, it was a crimson red, knee-length, V-neck... one piece dress. I had breasts as well, so I suppose this confirms the fact...

I'm a woman!

"Well, it appears you're right, gramps. I'm Maris..." well, I suppose I can't confirm that... after all I only know I'm a girl. However, it makes sense in two ways:

1. Why I am in Luffy's body. Firstly, Luffy is already here and it would certainly be odd if I was in his body just randomly! There's no real sense behind. If I died being born as Maris and my spirit was transferred into Luffy due to me being born with Haki, then I'm sure it makes a lot more sense.

2. Garp even claimed my Haki was similar to Maris', if that's the case then I suppose there's even more of a reason to say that I'm Maris. It would be an incredible coincidence if it wasn't true.

"Ahaha, who would suspect that my grand-daughter would be so strong to be able to beat me! Maris, make sure that Luffy becomes a strong marine!" I suppose I can say that the rule of arguing with those who possess the name of 'Monkey D.' is completely out the picture since I'm apparently one.

"But, gramps, what if I want to be a pirate?" I argued back at him, he then got agitated at my response.

"Rubbish! You two shall become amazing marines!" Well, even if I argue with him the result won't change, so it is really pointless.

"Well, I suppose I should get some rest. I'm going to head out tomorrow with my Mugiwara." I spoke the name which Luffy knows me as, I even thought of heading back to the Domain, but it didn't work.

"Oh, doing some exploring, huh?" Garp questioned. Well, I suppose there might be some problem, or it's possible that I've gotten a name change. By that I mean... it's no longer Mugiwara to enter and exit.

"Well, maybe exploring is a trait of being Maris." It worked. With the thought of entering the Domain and the new name I was able to enter the Domain!

My face... it feels smaller than it used to, my body also feels lighter as well. Now that I look down at my skin, it's exceptionally pale as well! My hair is also past my shoulders, this all equates to one thing. I've become a girl in the Domain.

I was planning on evaluating a few things and even discussing the issue with Luffy, however it appeared as if my body was being suffocated. I was being filled up with something that felt a bit too over-compensating. However, in that situation I was able to stand up, struggling might I add, but it appeared that some of the side-effects were able to be inadequate if I just went against them. I suppose Haki is to thank for that.

Then again, the choking feeling and while I was struggling, if that was something normal I suppose Haki would've been enough to actually deal with it, however if it was Haki itself then that would change the situation completely. If that's the case then perhaps I... improved my Haki an astounding amount from just the realisation of being Maris. At this point it might as well be a fact. However why it happened is a big question, I possibly need to do some research into my past.

"TWIN SISTER!" Huh, if it isn't Luffy. It appears he watched the entire thing, he approached me as if he was angry, why that was is unknown. "YOU LIED AND SAID YOU WERE MY TWIN BROTHER!"

Wait, is that why he's angry? He is upset that I lied to him about my gender? I mean, I'm a literal girl in the Domain right now couldn't he take that as a hint that I didn't know before hand? Well, I should probably remember I'm talking to an incompetent brother.

"Luffy..." I stood up from suffocating and hit him on the head. "DON'T TRY TO LECTURE YOUR SISTER!"

"AGGH! IT HURTS WORSE THAN JII-SAN'S!" Actually, after this scene I think I am uncannily related to these people. Then again, I don't think I've ever said such a thing with so much emotion, perhaps the Haki boost I just got or the realisation of being Maris triggered something in me.

There is also something else of concern.

I looked down below, to see what I was wearing. It was definitely what Luffy was wearing, the white shirt which has 'Anchor' on it and the blue shorts.

I thought my clothes would change, but it looks like I just officially became a girl again.

"Do you think I knew beforehand of my own gender? If so then I would've told you so, there's no point in trying to doubt me!" It turned to me lecturing him, he nodded unwillingly and sat down while crossing his legs.

"Does that mean your name is Maris then? Also, what did Jii-san talk about?" Luffy began questioning me.

"Yeah, I'm Maris now, don't forget it." While that was the easier part, I don't think discussing what me and Garp discussed is relevant to Luffy, I might tell him when he's older. My reasoning for this is because of Luffy's nature, I've read the manga and watched the anime enough to know that if I say: 'I'm your twin-sister who died after being born and my spirit was transferred into you', something bad will happen. "Don't worry about the conversation between me and gramps, it's nothing important."

A/N:

Yup! IT'S A GIRL!

Well, I have sixth chapter, but I'll post it after I've done the seventh, I like to be prepared for these things. :P