Luffy was going to out to sea to become a pirate but first he punched the sea king that ate Shanks arm and y/n was with the others waving luffy good bye the village chief was angry at luffy and ace becoming Pirates buy was happy that y/n wasn't becoming one because he's becoming a marine and was waiting for Garp to pick him up in a few days from now.
Village chief: I can't believe those two will become trouble makers.
Makino: don't worry I'm sure they'll be fine.
Y/n: yeah Ace left me and luffy when he was 17 and now me and luffy are now 17 and he has a head start to his dream.
Village chief: Still I'm glad your becoming a marine and not a pirate.
Y/n: My path is different from my brother's but we will meet again but not as brother's but as rivals.
Makino: It's sad to see good brothers fighting against each other but I still can't believe I won't see you guys again.
Y/n: Don't worry luffy and ace won't be around here very often but I'll promise to visit you when I have the chance.
Makino: I hope so.
Dadan: I'll see next time kid. Don't die out there.
Y/n: I won't dadan. Thanks for the memories.
Dadan: No problem kid.
A few days have passed and garps ship has docked and a few marines were following him.
Y/n: hey grandpa you here to pick me up?
Garp: yes and I would like you to meet these two young man. This is Coby and helmeppo, and kids this is my other grandson Y/n.
Coby: Wow! You look like Luffy-san!
Helmeppo: Are you his twin?
Y/n: Yeah I'm his twin brother.
Coby: Amazing!
Helmeppo: This is so cool seeing an identical twin in person.
Garp: Ready y/n?
Y/n: Of course I am grandpa.
Coby: I can't wait for this!
Y/n and Garp rode on his ship and sailed to the marine base where Sengoku was visiting.
Garp: Hey Sengoku I want you to meet my grandson!
Sengoku: huh? so you've caught straw hat?
Garp: No this is his twin brother y/n.
Y/n: Nice to meet you.
Sengoku: God damnit Garp I thought you've caught straw hat.
Garp: Sorry.
Y/n: So what about my brother?
Sengoku: Your brother is becoming more of a Trouble maker like your grandpa over there.
Y/n: Well you can't expect their to be someone in our family to be sensible.
Sengoku: Yeah I should have now what was going to happen. Anyways are you becoming a marine?
Y/n: yeah i'm becoming a marine i have a different path than my brother but it doesn't mean we won't greet each other when we see each other in the battlefield.
Sengoku: please don't become a mini garp junior.
Garp: Hey!
Y/n: no promises.
Sengoku: I will die either by garps hands or the avalanche of paper work.
???: Um excuse me.
???: i'm here to apply as a marine.
Garp: Wow you look like a mini tashigi.
???: You mean my sister? yes she applied a few years ago.
Y/n: Hello my name is y/n. what's yours?
Maya: my name is maya nice to meet you.
Garp: Yeah, yeah. by the way don't you have a sword?
Maya: No i can't afford one unlike my sister.
Y/n: Hey grandpa goku do you have any sword in here or not
Sengoku: Yes there is...Wait grandpa goku?!
Garp: Hahahahahaha...!!!
Sengoku: It's not funny garp!
Garp: It's not? Then it's Hilarious!
Sengoku: Ugh...there at the hall pass the court yard.
Y/n: Thanks grandpa goku. Come on maya let's take a look!
Sengoku: I'm not a grandpa!
Maya: Okay let's go!
Coby: Wow it's like i'm with luffy again.
Sengoku: Garp Stop Laughing!
Garp: Bwahahahaha...You may look young but to him your like me.
Sengoku: Shut Up!
With y/n
Y/n: So your sister is a marine? where is she?
Maya: I don't know i only know she's with a man name Smoker.
Y/n: You mean captain smoker?
Maya: you know him?
Y/n i never met the guy but he was in the list of promotion in my grandpas boat.
Maya: Really that's cool.
Y/n: Yeah. here we are.
Y/n open the door and saw a room full of guns, swords and cannons alike.
Y/n: Let see if they have a katana here.
Maya: Okay.
Maya and y/n search the entire room until they found two katana.
Maya: I call this one!
Maya: Wow it's so pretty!
Y/n: That just leaves me with this one i guess.
Y/n: Why is this one made from copper?
Maya: It's rare to see a copper katana. all the katanas are steel or even iron but copper is a rare one.
Y/n: Well guess i'm lucky...sort of?
Maya: Yeah maybe your right. do you want to spar with me for a minute.
Y/n: Sure it doesn't hurt to try.
Y/n and Maya went to the court yard and began to spar y/n was rookie in using swords but he had some good form while maya was experience and landed blow after blow good thing y/n is a devil fruit user or it would have gone south.
Maya: Your a devil fruit user aren't you?
Y/n: Yes i am, why?
Maya: i was asking cause your body suddenly turned into candy syrup.
Y/n: Yeah cause i ate the ame ame no mi while my brother ate the gomu gomu no mi so we have different powers and we made different techniques.
Maya: Like what?
Y/n: I'll show you. Ame Ame no: Sticky Geyser!
y/n planted his hand on the ground and made a candy syrup geyser but it was boiling hot and it harden over time.
Maya: That's one sweet devil fruit. no pun intended.
Y/n: Yeah it is.
Coby: So cool!
Helmeppo: Now that's cool.
Garp: See he's a natural.
Sengoku: well if he use it in a crowded area then he'll accidentally hit someone by accident.
Garp: Don't worry they be trained by me and they become the best marine imaginable.
Sengoku: I hope so.