Gelu

Biodata

Feature	Information
Name	Gelu (格鲁) 31
Alias(es)	Little Treant; Tree Giant; Wolf Gelu 29 71
Species/Race	Treefolk / Treant; a mutated product of Rono's Devil Fruit ability 31 95 199
Gender	Male 28 33
Age	Approximately three years old 204
Affiliation	Red Devil Pirates; Wolf Family 29 69
Occupation/Role	Crew member and frontline defender of the Red Devil Pirates 43 87
Bounty	80,000,000 Berries 71
Status	Active 220

Power Progression

Stage / Realm / Level	Chapter	Notes
Unnamed sea-derived skill	32	Absorbed a skill from the sea and grew one centimetre taller.
Initial Tree Giant combat manifestation	43 44	Enlarged while fighting the Arlong Pirates; his hardened skin resisted fish-man attacks, while thorns erupted from his body to strike enemies.
Post-battle physical growth	57	Grew significantly taller after killing numerous opponents, though prolonged fighting exhausted him and forced him back to his original form.
Battlefield armor control	87	As a Tree Giant, covered allied Donquixote members in protective wood armor and demonstrated resistance to flames.
Massive emotional manifestation	95	In response to Rono's apparent death, expanded into a Tree Giant roughly one hundred metres tall.
Conscious transformation control	181	The system recorded that he could consciously control his Tree Man Warrior transformation rather than relying solely on emotional stimulation.
Resin coating	199	Demonstrated the ability to coat the Red Devil with resin for its descent to Fishman Island.

Background

Gelu is a young Treant whom Rono treats as his son. He initially communicated almost entirely through “Gelu Gelu,” but began learning human speech during the crew's early voyages, proudly managing to call Rono “Dad” despite struggling with pronunciation 31 33.

He is connected to Rono's Devil Fruit ability: Rono identifies him as one of its products, while the system later describes him as a mutated product. This connection made seawater especially dangerous during the fight with Jinbe, as Rono believed Gelu would disappear upon touching the sea 69 95.

Gelu accompanied Rono and Sairona during their campaign against pirate crews around Alabasta. He participated in the assault on Arlong Park, where his defensive body and thorns allowed him to roll through groups of fish-men with little injury 43 44.

Appearance

In his ordinary form, Gelu is a very small Treant; he was once described as only 52 centimetres tall. His body has yellowish-brown hands marked with flame-like patterns, and he is often depicted with fiery red hair or a flame-like head 47 95 168.

• His skin is inherited from the Strange Tree and is notably durable 44.
• He can transform into a Tree Giant over ten metres tall; under extreme emotional strain, he has reached roughly one hundred metres 95 202.
• He sometimes wears a dinosaur suit 206.
• His Tree Giant form has been equipped with wood armor, a vine vest, and a khaki bulletproof vest 189.

Personality

Gelu is childlike, affectionate, and strongly attached to his family. Food—particularly meat and ice cream—is one of his greatest interests, and he becomes genuinely distressed when his treasured plate, spoon, food, and juice are ruined 31 162 220.

Despite his age, Gelu is fiercely loyal. He attempted to fight Jinbe to aid Rono, transformed in rage when Dragon appeared, and attacked opponents he believed had harmed his father 69 95 202. He also has an independent streak, wandering into a forest by himself and inadvertently becoming the target of Timothy Hood 163.

He can be thoughtful and polite when he understands the importance of a gesture. After Rono repaired Hancock's broken tableware, Gelu returned the plate and spoon to her with a red rose as thanks for caring for him 168.

Abilities & Skills

Tree Giant Transformation

Gelu can transform into a powerful Tree Giant. The system initially described the transformation as highly likely to occur under emotional stimulation and as requiring no stamina; later, it recorded that he could activate and control it consciously 86 181.

• His giant form grants exceptional physical strength; he seized Dragon by the tail and smashed him into the ground 202.
• He can manifest at drastically different scales, from over ten metres to approximately one hundred metres during an emotional outburst 95 202.
• His rage can drive him to attack relentlessly, as seen when he targeted Kizaru and later Shanks after Rono's apparent death 95.
• Extended fighting has nevertheless exhausted him enough to revert to his smaller form and fall asleep 57.

Vegetation Manipulation and Defense

Gelu can produce and shape plant-based defenses and appendages in both regular and giant forms.

• He can erupt thorns from his body to damage groups of enemies at close range 44.
• He covered Donquixote Family members in wood armor during the battle against Ryokugyu 87.
• His own layered defenses have included Wood Armor, a Vine Vest, and a bulletproof vest 189.
• He can extend vines from his hands to move heavy objects, including Nami's treasure 206.
• He used vines in an attempt to strangle Sanji during the clash with the Straw Hat Pirates 202.

Fire Resistance

As a peculiar tree species associated with volcanic conditions, Gelu is unaffected by ordinary flames. Ryokugyu specifically noted that Gelu could withstand fire despite being a Tree Giant 87.

Cannonball Deflection

During the battle against the Vinsmoke forces, Gelu blocked and redirected incoming cannonballs without detonating them 185.

Resin Coating

As a Treefolk, Gelu can produce resin to coat ships. He coated the Red Devil himself, enabling the crew to descend toward Fishman Island 199.

Connection to Rono

Rono shares a faint connection with Gelu that allows him to locate Gelu when separated. Rono has also noted that Observation Haki does not seem to perceive Gelu as a separate presence from himself 163 176.

Equipment / Items

• Bracer — Part of a matching father-son set made by Axia; Gelu wore it when departing Nine Snake Island with Rono 174.
• Small plate, spoon, knife, and fork — Tableware made for Gelu by Hancock. Rono repaired the broken plate and bent spoon using Earth Manipulation 162 163.
• Dinosaur suit — Clothing worn while helping Nami organize treasure 206.

Relationships

• Rono — Gelu's father figure and Devil Fruit creator. Gelu calls him “Dad” and fiercely protects him, while Rono repeatedly prioritizes Gelu's safety in battle 31 69 88.
• Sairona — His “Uncle” and a dependable caretaker. Sairona cooks for him, keeps him safe during Rono's reckless sailing, and later teaches him to speak properly 30 45 219.
• Axia — Maternal figure whom Gelu calls “Mother.” She regulates his ice cream, made his bracer set, and is credited with his good upbringing 157 168 219.
• Nami — His “second aunt.” She rewards his help, manages his treats, and relies on his vines to move treasure 206.
• Boa Hancock — Gelu calls her “Great-aunt.” She made his treasured tableware, and he later gave her a plate, spoon, and red rose in gratitude 162 168.
• Donquixote Doflamingo — Saved Gelu from falling into the sea during Jinbe's attack, earning Rono's declaration of lifelong friendship with the Wolf Family 69.
• Rayleigh — Tried to comfort Gelu after his tableware was destroyed and joined the search when Gelu wandered into the forest 162 163.

Story Role / Major Arcs

Early Red Devil Pirates Voyages

Gelu serves as Rono and Sairona's small but active companion while learning to speak. He joins the crew's voyage toward Alabasta, absorbs an unknown skill from the sea, and takes part in the campaign against the Shark Pirates and Arlong Pirates 31 32 43 44.

Jinbe Incident

Gelu attempted to help Rono against Jinbe but was kicked toward the sea. Doflamingo rescued him at the last moment, preventing his disappearance and triggering Rono's berserk retaliation 69.

Green Bit Battle

During the conflict with the Marines, Gelu transformed into a Tree Giant to fight Ryokugyu alongside Rono. He reinforced allies with wood armor, resisted flame attacks, and later became a massive giant when Rono was believed dead after Akainu's assault 87 88 95.

Nine Snake Island

While Rono and Rayleigh trained Luffy, Gelu remained part of the group’s domestic life, including the food fight that destroyed his tableware. His disappearance into the forest led Rono and Luffy into Timothy Hood's trap 161 162 163.

Vinsmoke and New World Campaigns

Gelu redirected Vinsmoke cannon fire, endured explosions behind layers of armor, and later coated the Red Devil for its journey to Fishman Island 185 189 199.

Clash with Dragon and Later Voyages

Gelu transformed into a Tree Giant during the confrontation with Dragon, severely striking the Revolutionary leader after he tried to escape. He later assisted Nami aboard the Red Devil and remained behind to protect her while Rono went to confront Big Mom 202 206 220.

Notable Quotes

“Dad...” 69

“Daddy, Gelu wants ice cream, lots and lots of ice cream.” 220