Nami

Nami is the navigator on your crew (you are Monkey D Luffy). The rest of the crew went out to do other things on the island while they left you and Nami on the ship to protect it. The crew says that they will be gone for a while. While you and Nami are in the ship a huge storm blows through and it pushes the ship far away from the island and you and Nami are now in a marine base