Douglas Bullet, called the "Demon Heir," was abandoned as a newborn in war-ravaged Galzburg and raised as a child soldier within the Galzforce military. All soldiers in this unit were assigned the surname "Douglas," with his specific designation being "Bullet." Enduring countless suicide missions from infancy, he survived against impossible odds, emerging as one of Galzburg's most formidable warriors by age nine. His battlefield feats earned him the Medal multiple times, but resentment from comrades led to betrayal. At fourteen, after nearly ending Galzburg's perpetual conflict, fearful superiors attempted to eliminate him. In response, Bullet annihilated the entire military force and destroyed Galzburg itself. During his youth, Bullet consumed the Gasha Gasha no Mi (Clank-Clank Fruit), a Paramecia-type Devil Fruit granting him the power to remotely disassemble and reassemble inanimate objects. Combined with his mechanical expertise, this allowed him to construct complex structures, including exoskeletons that augmented his physical abilities. At fifteen, he encountered Gol D. Roger, the only person to ever defeat him. Despite repeated challenges, Bullet lost every battle but developed profound respect for Roger, eventually joining the Roger Pirates. His strength during this period was comparable to Silvers Rayleigh, Roger's first mate, with speculation he surpassed Rayleigh through relentless training. Bullet viewed camaraderie as weakness, rejecting Roger's belief that friendship amplified strength. Learning of Roger's terminal illness, he left the crew at eighteen, concluding his final duel with the captain. Following Roger's execution, Bullet embarked on a destructive rampage worldwide. His threat level escalated to the point where the Marines initiated a Buster Call specifically targeting him, led by Admirals Sengoku and Monkey D. Garp, and enlisted pirates he had assaulted. Though ultimately captured, Bullet inflicted massive casualties before imprisonment in Impel Down's deepest level. He remained incarcerated for over 20 years, honing his abilities. During a mass breakout instigated by Monkey D. Luffy and Marshall D. Teach, Bullet escaped. Bullet later allied with Bueno Festa, a pirate from Roger's era, to dismantle the "New Pirate Era" Roger inspired. At the Pirates Festival, he orchestrated a confrontation to lure the world's strongest pirates, including the Worst Generation and the Four Emperors. Utilizing his awakened Devil Fruit powers, he restructured an entire island into a colossal mechanical construct to demonstrate supremacy. He effortlessly defeated nine members of the Worst Generation and overwhelmed a Marine-led coalition of pirates, revolutionaries, and Warlords. His awakening allowed manipulation of landscapes on a massive scale and merging with metallic structures to form a gigantic combat form. Despite his physical and strategic advantages, Luffy's "Gomu Gomu no King Kong Gatling" attack destroyed his mechanized body and rendered him unconscious. His subsequent fate remains unspecified, though reimprisonment in Impel Down is implied. Physically, Bullet is a towering, muscular man with broad shoulders, slicked-back hair, and a prominent scar extending from the left side of his face to his chest. Tattoos adorn his left arm. He typically wears a medal-adorned collared shirt, belt, pants, boots, and headphones. His personality is defined by aggression, combat obsession, and a belief that absolute strength negates the need for alliances. Traumatized by repeated betrayals—first by Galzforce comrades, later by fellow pirates—he considers interpersonal bonds detrimental. He equates the title of "Pirate King" with unrivaled power, seeking to claim it by eliminating all rivals. Bullet's combat abilities rank among the world's elite. His physical prowess includes immense strength, speed capable of matching Luffy's Gear 4 Snakeman form, and durability allowing him to withstand powerful attacks without significant injury. He employs Rokushiki techniques like Soru (high-speed movement) and Geppo (air-walking). Beyond his Devil Fruit, he wields Haoshoku Haki (Supreme King Haki) capable of knocking out hundreds simultaneously and Busoshoku Haki (Armament Haki) to enhance attacks.