One Piece Chapter 41, page 11-12: To the Sea

Usopp grins at Kaya and promises, "NEXT TIME I COME TO THIS VILLAGE, I'LL TELL YOU ADVENTURE STORIES THAT ARE MORE UNBELIEVABLE THAN LIES." Kaya smiles warmly and replies, "THANK YOU. I LOOK FORWARD TO IT." Usopp then turns to the Straw Hat crew and waves, saying, "WELL, SAFE VOYAGE GUYS! HOPE TO SEE YOU AGAIN SOMEWHERE!" Luffy looks at him blankly and asks, "WHY?" Usopp is taken aback: "HUH, WHY? SHEESH... YOU'RE SUCH A COLD HEARTED MAN... WE'RE BOTH GOING TO BE PIRATES NOW, SO WE MIGHT MEET AGAIN ON THE HIGH SEAS..." Zoro, sitting on the ship's railing, calls out, "WHAT ARE YOU TALKING ABOUT... HURRY UP AND GET ON BOARD!

Luffy looks down at Usopp with a wide, friendly smile and says, "YOU'RE ALREADY OUR COMPANION, AREN'T YOU...?" Usopp freezes in shock, his eyes wide as he stammers, "WHA...." Realizing they want him to join their crew, his face lights up with joy. He runs toward the ship, pointing proudly at himself and shouting, "I... I'M THE CAPTAIN RIGHT!?" Luffy immediately yells back from the deck, "NO WAY! I'M THE CAPTAIN!!" while Kaya and Merry watch them with warm smiles.