One Piece Chapter 50, page 6-7: TO EACH HIS OWN WAY

Johnny and Yosaku scream from the water, "W-WAIT A MINUTE, SIS! WE WERE ASKED TO KEEP A WATCH ON THAT SHIP! YOU'RE PUTTING US IN A LOT OF TROUBLE HERE! AND GIVE BACK OUR TREASURE!" Suddenly, a massive crashing sound ("ドゴォン!!") shakes the area. Luffy, Zoro, and Usopp are on the deck of the Baratie. Johnny and Yosaku explain what happened: "AFTER SAYING THAT, SHE RAN AWAY!" Usopp is furious, yelling, "DAMN THAT WOMAN! JUST BECAUSE SHE WAS ACTING ALL NICE RECENTLY, I LET MY GUARD DOWN FOR ONE MOMENT AND THEN THIS HAPPENS! HOW DARE SHE PULL A FAST ONE OVER US, ESPECIALLY DURING THIS CRISIS!

Luffy looks out across the water, holding his straw hat. "WAIT! I CAN STILL SEE OUR SHIP!" he shouts. Usopp and Zoro look in shock as Luffy points: "IT'S THE GOING MERRY!" Luffy turns to Johnny and Yosaku: "YOSAKU! JOHNNY! WHERE'S YOUR SHIP!?" They reply, "WELL, WE STILL HAVE OURS." Zoro tells Luffy, "ZORO! USOPP! JUST LET HER GO. NO GOOD WILL COME OF CHASING AFTER THAT THIEF." Usopp protests, "B-BUT SHE TOOK OUR SHIP! THAT SHIP'S IMPORTANT!" Luffy looks incredibly determined and declares, "I WANT HER TO BE OUR NAVIGATOR, NO MATTER WHAT!