DISCLAIMER: One Piece and everything affiliated with it belongs to Eiichiro Oda Shonen Jump, etc. All I own is the plot…
You aren't sure why you're fighting, but you do know that the Hairy Man you are fighting is a Bad Man who tried to hurt Your Crew, so you don't really need any more of a reason. In the meantime, Your Crew is fighting with the Hairy Man's crew, but you know that you don't have to worry about them because they are strong and wonderful and good—otherwise, they wouldn't be Your Crew, would they?
Then, suddenly, you are tingling all over and then everything is bigger much much bigger and you think you must be smaller much much smaller but you can't think why because you're pretty sure you only get smaller much much smaller when you've done…something. But for some reason you can't remember what that something is.
But then you hear laughing and you are sure laughing is a good sound but it's coming from a Big Hairy Man and you're pretty sure he shouldn't be laughing because he smells funny and it's not a good funny which means it must be a bad terrible awful funny which means he is a Bad Man and he shouldn't be laughing.
So you growl at him, low in your throat, and your hackles raise, and you leap forward to bite him but he swipes you out of the way and you think you hear someone yell your name but you can't be sure because everything is going black black black...
...When you wake up again everything is soft and comfortable and warm and it smells very, very clean wherever it is. So you sit up and yip yip yip because you can't get down, the floor is so far away! And then someone comes and they are furry just like you but not like you because they smell like a different kind of furry and they say something but you are too excited about people people people to pay attention so you just wag wag wag your tail and bark some more until another someone swipes your nose.
But oh oh oh you know this someone by heart because this is Zoro who smells like steel and sweat and seaweed (which you think should be funny for some reason but you can't think why it should be funny until you smell cigarettes and MEAT! and spices and MEAT! and then you know that that is Sanji and Sanji calls Zoro seaweed and that is why Zoro's smell is funny) and Zoro is yours and you love love love Zoro because he is your Zoro, yours only yours. So you jump at Zoro because you always have always will jump on Zoro when you see him, but for some reason you can't hold onto him like you think you should be able to, so it's only him catching you that stops you from falling onto the floor.
He catches you by the scruff of your neck though and that hurts a lot, so you whine and curl up because you think you did something bad and you hate hate hate it when you do something bad that makes Zoro angry because Zoro is your Zoro and he should never be angry at you.
When Zoro brings you up to his face, you see that he is not really angry (that tilt at the edge of his lips always means he is not really angry) but is probably trying to be (you can't think why he would try to be angry because Zoro should always be happy happy happy), and even though you sometimes play along with him you can't because you really thought he was mad this time and you are so excited he isn't that you start wagging your tail again and would lick lick lick him all over his face if you could reach but you can't so you just grin at him instead.
He says something but you don't remember what the words mean except for Luffy (because that is your name), and then he passes you to someone else with a sigh sigh sigh that makes you stop wagging your tail and start whining again.
The person you have been passed to doesn't hold you by the scruff of your neck like Zoro did, but instead cradles you in their arms which is really comfy but Zoro's smell is leaving so you wriggle around until the person—who smells like oranges and paper and ink and oh that's Nami—lets you go with a soft curse.
You tumble to the floor but it only hurts a little so you ignore it because right now it's more important that you find Zoro's smell again. You sniff sniff sniff until you smell metal and you follow the smell but oh, it's the wrong kind of metal, because this metal is mixed with wood and something tropical and it must be Franky. You know you're right, because before you can run away you have been scooped up into his big bigger biggest arms and even though you wiggle and jiggle around he won't let you go. He just takes you back to the soft and comfortable and warm place and sets you down and then the fuzzy person who smells like medicine and Chopper! It's Chopper! starts poking and prodding you and it feels funny and you want to go find Zoro so you can play play play and make him stop sighing but Chopper won't let you go why won't he let you go you want him to let you go but he won't why won't he?
You try to bite him, but you get swiped again and this time it isn't by Zoro it's by Nami, and then there are lots of arms holding you down and they smell like musty old stuff and parchment and leather and you decide it's probably Robin and Robin's really smart so if she wants you to stay still you probably should but you don't want to because Zoro! but you do anyway because it's Robin and Robin is part of Your Crew and if she thinks you should be still then you will even though you don't want to.
The poking and prodding starts up again but this time you stay still because Robin and Chopper want you to stay still and it tickles tickles tickles but you can't move, can't shouldn't won't. And then finally you can move because the arms are gone so you do and then the arms grab you again and take you to the floor. You yip happily at Robin's smell and then run run run because you're free free free and weren't you going to do something? OH! That's right you were going to find Zoro but then Sanji says something that sounds suspiciously like MEAT! MEAT! MEAT!
It smells really really really good so you follow Sanji's smell instead of Zoro's and Sanji sets a big giant enormous piece of meat in front of you and you bark with joy and start eating it and it's tougher than usual because your teeth are smaller than usual but you eat it anyway and then it's mostly gone but there's still some left on the bone so you nibble gnaw chew on the bone until the bone splinters and Chopper's smell takes it away.
You're upset that Chopper took away your bone and briefly consider chewing on him as a replacement, but Chopper is only for Emergencies and it isn't an Emergency and that means he's part of Your Crew. So instead you chew on the table until you hear a loud shout and smell Sanji's smell and you have just enough time to think that maybe chewing on the table wasn't such a good idea before Sanji has kicked you.
The kick sends you farther than you think it usually does, and when you hit the water you become much more scared frightened terrified than usual because you are sinking really fast and you can't breathe and you're so heavy you can't move and what if Sanji kicked you so far away that no one will reach you in time? And then you hear splashing and then nothing and then you are held close close close to someone's chest and when you break the surface of the water you can breathe again and it's Zoro's smell and you are so happy that you lick lick lick him all over his face like you wanted to earlier.
When you and Zoro get pulled back onto the deck Sanji's smell comes close and you hear words that sound familiar but not really and then Zoro is saying something back but you are just so happy to be away from the scary water and with Zoro and Your Crew again that you can't do anything but lick lick lick anything that comes near your mouth and wag wag wag your tail.
And then, once your happiness has faded a bit, you become sleepy tired exhausted, so you flop down onto the deck and start to sleep.
When you wake up again you are warm and happy and safe. You are in a different place than before, but you like this place better because it has Zoro's smell and then you realize you are on Zoro and you remember that you made Zoro angry before but if he's letting you sleep with him again then he must not be angry anymore, right? So you almost get up and start barking and licking so that he knows how happy you are but when you look outside it's dark and you think that Zoro should sleep when it's dark because he trains trains trains so much when he's awake and he saved you from the deep dark terrible ocean today so he must be really tired, right? You decide not to bark and lick or at least not to bark because you snuggle closer closer closer to his face and lick his cheek a few times until he swats at you and then you nuzzle his cheek and go back to sleep.
This time when you wake up you are too hyper to stop yourself from barking and licking and wiggling around and Zoro grumbles mumbles mutters at you but you don't care because he isn't angry at you just annoyed irritated agitated and the sun is up so he should be up too and maybe you can finally play with him! When he gets up and puts you on the floor you bark whine whimper until he gets up, too, and then you run around and around and around him until you're dizzy dizzy dizzy and you trip over yourself and fall.
But Zoro laughs laughs laughs and that makes you very happy so you stumble to your feet and crouch and pounce on his foot and then run away when he tries to grab you. And he chases chases chases you all over the ship until Nami's smell shows up and says something that makes Zoro stop and grumble and walk off and you want to go after him but she picks you up and takes you to the kitchen and ooh there's MEAT!
So you eat devour inhale until you can't move anymore so instead of moving you lay out and watch Your Crew eat breakfast which smells really good and maybe you could fit a little more food into your stomach? And then someone comes close to you who smells like gunpowder and fear and that definitely makes it Usopp's smell and you think of growling just to scare him but he brought you more MEAT! So you don't, you just grin at him and start eating some more even though you thought you were full before but who cares because it's MEAT! and MEAT! is good wonderful glorious.
And then you really can't move anymore, so you flop down and roll over and over until Usopp scratches your tummy and it feels so good that your leg starts scratching of its own accord which makes Usopp giggle and scratch more and then more smells are coming closer and lots of people are scratching your tummy and laughing and having a good time and you are happy delighted exhilarated because when Your Crew is happy then you are happy and they are all very happy right now.
And then, suddenly abruptly inexplicably they aren't happy anymore, they're angry furious scared because someone has shot at them and then the last of Your Crew, the one who smells of music and BONES! (you didn't think so before but now you think BONES! are almost as good as MEAT! but you also think he is probably for Emergencies like Chopper is so you don't bite him like you want to) and that's Brook's smell, and he's yelling about a word (marines) that sounds familiar and makes your hackles raise and then there is shooting and shouting and fighting and someone hurt Your Crew!
And more importantly the part of Your Crew that they hurt was Zoro and you are so angry that you puff up up up until you are the size you remember being originally and then you yell words (words! You remember words, now!) and punch all of those mean nasty terrible guys off of Your Ship and away from Your Crew and you hope they all drown for hurting Your Crew but you don't think any of them are Devil's Fruit users so you don't think they will, Goddammit.
You run over to Zoro and oh, oops, he wasn't hurt all that bad and he's actually a little angry that you bashed all of those Bad Guys off of the ship, but you don't care because you were really scared that he was hurt because boo-boos look a lot bigger when you're a lot smaller. So you wrap your stretchy arms (oh! That's why you couldn't grab him last time! You didn't have stretchy arms!) around and around and around him and hug him really tightly until he sighs (but it isn't a sad sigh this time) and hugs you back.
And then all of Your Crew is hugging you again, and you're so happy that you wish you had a tail to wag but you don't, so instead you lick Zoro's cheek and laugh loud louder loudest and Your Crew laughs with you and everything is right and good and wonderful again.