"Warrior" Leo

Leo shares the dwarf build: diminutive, with a large bushy tail and a pointed nose. His brown hair grows long, and he wears a green hat resembling a crown with one of its points folded over. His original getup adds a green jumper, goggles, a red tie, plus beige boots and gloves, and he commonly lugs around a gun nearly his own size. Upon turning pirate he dons a dark pirate coat and a hat bearing the jolly roger of his crew plus two feathers along its left flank, and he now carries a cutlass.

Leo conducts himself like a warrior, a fitting trait for the commander of his kingdom's army, and he obeys Tontatta law strictly, once demanding that Robin surrender either a weapon or her clothing to earn release. His fellow dwarves rely on him to lead them into combat. He is enormously gullible all the same, and an added streak of obliviousness leads him to read Princess Mansherry's flirting as plain selfishness rather than fondness. His grasp of Devil Fruits runs so thin that he calls both his own ability and Robin's mere magic. He is upright and brave nonetheless, refusing to accept Trebol's accusation that Usopp had deceived them and squaring off against the World Noble Charlos to defend Shirahoshi.

Leo consumed the Nui Nui no Mi; this Paramecia fruit lets him stitch together objects and living beings alike using a needle and thread. The needle passes through anything without harm and can be undone just as cleanly, while the binding holds tightly enough to pin a person down or fling foes into one another. He wields these needles as makeshift blades, practices Tontatta Combat, and like all dwarves boasts great strength, swiftness, and a knack for cultivating plants.

On Green Bit, Leo confronted a band of Marines and stripped them of their gear, then helped seize Robin and Usopp and bring them down to the Tontatta Kingdom, pinning Robin with stitches so the dwarves could search her. Once persuaded she meant no harm, he released her. After the dwarves grew convinced that Usopp descended from the hero Mont Blanc Noland, they recruited him to spearhead their war on the Donquixote Family. The dwarf army filed through underground tunnels into Dressrosa for Operation SOP, set on freeing their five hundred enslaved kin at the SMILE Factory and toppling Doflamingo. Leo's plan to slip Sugar a grape-shaped lump of fiery Tatababasco unraveled when she turned several dwarves into toys and Trebol scattered the rest with an explosion. Battered though he was, Leo kept faith in Usopp, who in the end downed Sugar and rescued the toy slaves, leaving the dwarves in tears and pledging him a statue.

When Doflamingo sealed the island inside his Birdcage, Leo rode the Tontatta Airlines beetles alongside Robin, Rebecca, and Bartolomeo toward the palace. There he and Kabu cut through enemies to rescue Mansherry, and Leo brought down the officer Giolla by sewing her own underlings onto her and yanking the thread to slam them into her. After Doflamingo fell, Leo stitched the pursuing Marines' ships together to cover the Straw Hats' escape, then handed his dwarves to Luffy, their band becoming the Tontatta Pirates and serving as the fifth vessel in the newly formed Straw Hat Grand Fleet. He went back to Dressrosa to oversee the carving of statues for Luffy, Kyros, and Usopp.

Reformed afterward as the Tontatta Pirates, the dwarves were tasked with escorting the Riku Family to the Levely. At Mary Geoise he met up again with Sai and befriended Vivi. When Charlos grabbed Shirahoshi, Leo and Sai knocked him out together, repeating the same strike during the Wano period when Charlos returned using Kuma, before they slipped away with Mjosgard's help. Around the Egghead events, Leo pressed Rebecca about the news surrounding Luffy and Vegapunk, and she assured him the damaging reports were false.