Nico Robin (ニコ・ロビン Niko Robin), also known by her nicknames Demon Girl (悪魔の子 Akuma no Ko) and Light of the Revolution (革命の灯 Kakumei no Tomoshibi), is the archaeologist of the Straw Hat Pirates, as well as one of the senior officers of the Straw Hat Grand Fleet. She is the seventh member of the crew and the sixth to join, joining at the end of the Alabasta arc.

She is introduced as one of the most prominent secondary antagonists of the Alabasta saga, being the vice president of Baroque Works and Crocodile's right-hand woman. However, after being saved from death by Monkey D. Luffy and the subsequent defeat of the former Warlord of the Sea, she joins the crew. He temporarily left the gang during the Water 7 arc, but rejoined at the end of the Enies Lobby arc following CP9's defeat at the hands of the Straw Hat Pirates.