Ichiban Ushiro no Dai Ma?, also known as Demon King Daimao, is a Japanese light novel series written by Shotaro Mizuki and illustrated by Souichi It?, published by Hobby Japan under their HJ Bunko imprint. The first volume was published on February 1, 2008, with a total of 11 volumes available as of December 2010. A manga adaptation began monthly serialization in the September 2008 issue of Akita Shoten's magazine Champion Red, and a 12-episode anime adaptation by Artland aired between April and June 2010 on Tokyo MX and other channels.

20 years after his escape from Impel Down, the legendary pirate Shiki, the Golden Lion, reappears causing massive upheaval to the Marines. During his long seclusion, he was able to come up with a scheme to bring the World Government to his knees. On his way to execute the plan, Shiki crosses paths with the Straw Hat Pirates and becomes so impressed with Nami's knowledge of meteorology that he abducts her to forcedly enlist her into his crew. Luffy and the gang end up on a strange land populated with monstrous beasts as they desperately search for Shiki and Nami.