One Piece Chapter 8, page 18: Nami

The pirates are furious, shouting, "WHY YOU... SCURVY BILGE-RAT!!" but Luffy quickly and easily beats them all up with his bare hands, leaving them unconscious on the ground. The girl, who was watching from a nearby rooftop, is amazed. She jumps down and says, "WOW! YOU'RE PRETTY TOUGH. YOU BEAT THOSE SABER-SWINGERS WITH YOUR BARE HANDS!" Luffy, still confused, asks, "UH... WHO'RE YOU!?" She smiles warmly and introduces herself: "THE NAME'S NAMI!! I SPECIALIZE IN ROBBING PIRATES. WANNA TEAM UP WITH ME!?" Luffy looks surprised, repeating, "ROBBING PIRATES?"