Screen 1 — Reverse Mountain
The Straw Hat Pirates sail toward the massive stone wall rising from the ocean — Reverse Mountain, the gateway to the Grand Line. Four ocean currents rush upward along its slopes, all meeting at a single point at the top before plunging down one enormous drop into the Grand Line.
Nami grips the wheel, fighting the raging waters.
Nami: "Brace yourselves! If we mess up even once, the Merry's finished!"
Zoro: "We're getting dragged up whether we want to or not!"
Sanji: "Hold the ship steady, Nami-swan!"
Usopp: "I DON'T WANT TO DIE BEFORE WE EVEN GET THERE!"
Papyrus: "THIS IS THE GREATEST WATER SLIDE OF MY LIFE!"
Sans stands at the railing, completely calm.
Sans: "heh. reverse mountain… didn't think the ocean could go up."
The Merry shoots over the peak and drops down the massive current on the other side, the crew screaming (except Sans).
Luffy: "We made it—THE GRAND LINE!"
But their celebration dies instantly.
BOOM.
The Merry crashes into something huge — a massive wall of black skin.
A giant whale blocks the entire exit.
Usopp: "WE HIT A MONSTER!"
Papyrus: "IS THAT A GIANT FISH!? NO—A GIANT WHALE!?"
Sans squints, unimpressed.
Sans: "uh… pretty sure the whale's not trying to eat us. more like… we're the ones bumpin' into him."
The whale slowly turns, eye the size of the Merry itself staring right at them.
Luffy: "IT'S LOOKING AT US!!"
The adventure in the Grand Line begins… with a giant surprise.
Screen 2 — Laboon's Story
The Straw Hats climb onto the strange metal structure inside the whale, stunned by the sight of an old man relaxing in a giant room filled with machinery.
Crocus: "Welcome. You're inside the whale."
Usopp: "INSIDE!? WE GOT EATEN!?"
Papyrus: "THIS IS EITHER AMAZING OR TERRIFYING! I CAN'T DECIDE!"
Sans looks around lazily.
Sans: "heh. kinda cozy in here."
Crocus introduces himself as the lighthouse keeper of Reverse Mountain, and soon explains the truth about the whale.
Crocus: "His name is Laboon. He's been waiting at the entrance of the Grand Line for fifty years… waiting for the Rumbar Pirates to return."
The crew falls silent.
Sanji: "Fifty years…?"
Nami: "All alone…?"
Papyrus: "THIS WHALE HAS A HEART OF PURE DETERMINATION!"
Sans gives a small nod.
Sans: "good whale. loyal. don't see that much these days."
Crocus eyes him.
Crocus: "A skeleton giving emotional support. Now I've seen everything."
Sans smirks.
Sans: "hey old man, at least i'm more comforting than your interior design."
Crocus fires back instantly:
"Boy, your hoodie looks like it crawled out of a thrift store bargain bin."
Papyrus gasps.
Papyrus: "A ROAST BATTLE!? SANS, YOU CAN'T LOSE!"
Sans slouches.
Sans: "nah, he's got fire. respect."
Crocus chuckles and the tension eases.
---
Luffy's Promise
Outside, Laboon keeps slamming his head against the mountain wall, crying out in pain.
Crocus: "He does this every day. He believes fighting the wall will reunite him with the friends he lost."
Luffy tightens his fist.
Luffy: "If you want to fight so badly… then fight me!"
He headbutts Laboon, stopping him in his tracks.
Papyrus: "LUFFY, YOU CAN'T FIGHT A WHALE WITH YOUR FACE!"
Sans: "that's luffy logic. don't question it."
Luffy then paints a giant Straw Hat Jolly Roger on Laboon's forehead.
Luffy: "We'll be back. And when we return, we'll fight again. So stop hurting yourself!"
Laboon lets out a soft, hopeful cry — his first in decades.
Crocus smiles quietly.
Crocus: "You gave him something new to wait for."
Sans pats Laboon's skin gently.
Sans: "hang in there, big guy. we'll swing by again someday."
Papyrus salutes dramatically.
Papyrus: "WE SHALL RETURN, LABOON! AND WE SHALL BRING SNACKS!"
The whale cheers happily as the Going Merry sails off into the unknown Grand Line.
Be continued