One Piece Chapter 9, page 21: Chapter 9: Femme Fatale

Nami turns back to Luffy with a sweet, manipulative smile, saying, "But you seem to really need a navigator, so I'll consider it on one condition." Luffy asks eagerly, "Really? What's your condition?" Nami holds up a finger and says, "Just a little thing. It's nothing, really. Go with me to see Buggy." Luffy, completely trusting her, grins and says, "You got it! Let's go! Where is this Buggy?" Nami tells him, "Hold on, I have to get ready." She then appears holding a thick coil of rope. Luffy asks, "What's that rope for?" Nami smiles innocently and replies, "Oh, I always carry a rope. So, you want to be a pirate, do you?"