Koby was first introduced as the Alvida Pirates' hapless ship caretaker who lived in fear of both the ship's crew and captain. Two years of forced servitude had robbed him of all hope of escaping as well as his dream of becoming a Marine, leaving him with few goals other than avoiding being bludgeoned to death by Alvida's iron mace. Luffy was less than impressed with Koby's cowardice, describing him as "pretty stupid and useless...and kinda wimpy too". However, Luffy's boundless optimism and single-minded pursuit of his dream rekindled a similar conviction in the downtrodden ship caretaker, allowing him to defy his captors, even under the threat of a brutal death by Alvida's mace.