A wiry rock gnome with weathered copper-brown skin, enormous expressive eyes, and a shock of tangled black hair tied beneath a faded blue sailor's bandanna. He wears patched scale mail sized for his small frame, a salt-stained green cloak, and a collection of tiny brass tools secured to his belt. His longbow is nearly as tall as he is, and his boots are decorated with bright scraps of sailcloth from ships he has served aboard.

Usopp is energetic, imaginative, and endlessly talkative. He presents himself as a legendary mariner and fearless monster hunter, but beneath the boasting is a sharp-eyed survivor with a genuine instinct for protecting the vulnerable. He prefers clever traps, distractions, and carefully chosen escape routes to direct confrontation, though loyalty can drive him into danger before he has finished making excuses.

Usopp was born in a cramped workshop built into the lower decks of a coastal trading vessel, where his parents repaired navigation instruments, locks, and enchanted compasses for passing captains. As a rock gnome, he was fascinated by every mechanism he encountered, but the sea taught him that the finest device was useless if its owner could not read the weather, follow tracks across a beach, or notice danger before it struck. He became a sailor, scout, and occasional deckhand, learning to move silently through rigging and mangrove shallows while keeping watch for pirates, monsters, and treacherous currents. During a voyage through a fogbound island chain, Usopp discovered an abandoned gnome observatory overrun by strange beasts. The crew wanted to loot it and leave, but Usopp stayed behind long enough to rescue a wounded creature and recover the observatory's star charts. Since then, he has wandered from ship to ship as a ranger, following rumors of lost coasts and unexplored islands. He claims he is searching for the greatest map ever drawn, though privately he hopes to find the truth about the vanished expedition that once used those charts. He is brave when no one is watching, boastful when everyone is, and completely unwilling to admit that both traits are true.