Douglas Bullet

Douglas Bullet also known as the Demon's Heir, is the main antagonist of the movie One Piece: Stampede. He was a soldier of his country until he was betrayed. He was a member of the Roger Pirates. He was a prisoner of Impel Down Level 6 until Marshall D. Teach freed him. He cooperate for the Pirate Festival to kill the Worst Generation and destroy the World Government to prove himself to be the strongest.

Personality
Due to growing up as a soldier in war torn childhood, Bullet values strength above all else, gaining solace in it while constantly hungering to get stronger. As strength is the only thing he cares about, he spends his time rampaging and battling everyone he encounters, fearing no one. Due to Gol D. Roger being the only person who has ever defeated him and his legendary status as the Pirate King, Bullet views the Pirate King as the strongest person in the world who can defeat anyone, and so seeks to kill the world's most powerful people in order to achieve the title. He has been shown to admire people who are stronger than him, though he still only seeks to eventually defeat them.[1][2]

He views friendship and camaraderie as detrimental to his pursuit of strength, due in part to being betrayed multiple times by comrades he had made while a member of Galzforce. Roger tried to show him that one is strongest when having friends to protect, but Bullet rejected this and sought solely to beat Roger while he was on the Pirate King's crew. Bullet later tried to prove that having friends was a hindrance when he forced Luffy to unsuccessfully protect Usopp.[1][2]

Like many other characters, Bullet has a distinctive laugh: "Kahahaha" (カハハハ?).