Brook is the living skeleton musician and ninth member of the Straw Hat Pirates, joining after the Thriller Bark Arc. His skeletal state resulted from consuming the Yomi Yomi no Mi (Revive-Revive Fruit), which returned his soul to his body after death. A fifty-year journey through the afterlife left only his bones intact, his distinctive afro preserved thanks to "strong roots". In life, he appeared as a tall, slender man sporting a goatee, sideburns, a diagonal forehead scar, and often sunglasses. Originally part of the Rumbar Pirates, Brook died and resurrected aboard their vessel, drifting alone in the Florian Triangle for fifty years until meeting the Straw Hats. His driving dream is to reunite with Laboon, the whale waiting faithfully at Reverse Mountain, fulfilling a decades-old promise. Post-timeskip, Brook stands 277 cm tall, ranking as the crew's second-tallest member after Jinbe. His attire evolves to match his "Soul King" persona, featuring flashy, colorful outfits complete with heart-shaped sunglasses, feather boas, and ornate top hats. In Wano Country, he wears a white kimono and samurai armor, later adopting Viking-style leathers in Elbaph. His personality mixes eccentricity with gentlemanly courtesy. Brook frequently cracks "skull jokes" (e.g., "I can't believe my eyes! Not that I have eyes!") followed by his signature "Yohohoho" laughter. Despite his vulgar habit of requesting to see women's panties, he maintains formal speech, often using respectful honorifics like "-san". He exhibits extreme emotional reactions, like panicking upon realizing he frightens others. Profoundly compassionate, he despises cruelty and those who waste lives, defending even enemies from unnecessary harm. His prolonged isolation fuels a deep appreciation for companionship, making him cherish simple acts like shared meals. Music defines Brook. He sings "Binks' Sake" to confront fear or sorrow, and his combat style integrates musical themes. His Devil Fruit powers grant extensive soul manipulation: he separates his soul from his body to scout areas, generates chilling energy to incapacitate foes, and interacts with souls through music, as demonstrated seeking help when captured during the Fish-Man Island Arc. In battle, he serves as one of the crew's two swordsmen, wielding a cane sword with ice-based attacks named after dances and songs. His loyalty is absolute. Brook risks his life protecting crewmates, like shielding Usopp from a Pacifista, and confronts emperors such as Big Mom fearlessly, addressing her contemptuously as "young lady". His chivalry compels him to defend women, though he fights them if necessary, seen against Giolla and Big Mom. While sharing Sanji's lecherous tendencies, he mocks others like Momonosuke for similar behavior. His bounties mark his growth: 33,000,000 berries from his Rumbar days, rising to 83,000,000 after Dressrosa, and 383,000,000 post-Wano.