Though not a samurai, he appears to maintain a certain degree of bushido, and is frequently mistaken for one. Unlike Luffy and most of the other Straw Hat pirates, Zoro has been known to kill his opponents if he has to, though never in cold blood. Zoro has a stern, serious and distanced personality, but, unlike Robin, he often reacts in a goofy and exaggerated comic style due to his gruff, impatient attitude. On the ship, he normally either trains with weights or sleeps. The only work he is seen doing regularly is hoisting the anchor using his great strength. He also likes sake, almost to the degree that Luffy likes meat, but like Nami, he never gets drunk due to his inhumanly-high endurance and tolerance for alcohol. Another notable trait is his lack of orientation, as Zoro often gets lost, even in small, familiar spaces or when being led by someone. Despite this, he is often the first to sense an enemy or danger, and the first to react. He is often displayed being well aware of dangerous situations and people around him. Zoro often also reminds others of the harsh facts, which often shocks some of the other crew members, although they usually decide he is right. Zoro has also stated that he is an atheist, and has never believed in anything except himself. He often comes across as arrogant and overconfident, but only because he knows he's a strong man with great fighting ability. Even so, Zoro knows that he still has a lot of untapped potential, and is constantly seen training and trying to improve his fighting skills. He also adheres to a strict sword master's code of honor, and never falsely brags or lies about his abilities, sometimes outright admitting a weakness, even to an enemy. He also never tries to escape from a fight or use trickery to win, believing that doing so is cowardly and scorning anyone who uses such tactics. Zoro is very vigorous, strong-willed, and determined.

Age (during the series): 17-23 Light, born on February 28, 1986, is a third-year high school student (12th grade) at Daikoku Private Academy (大国学園, Daikoku Gakuen) who also attends supplemental classes at Gamou Prep Academy at the beginning of the story. Light has a father, Soichiro Yagami, who is the head of the Police Force. Light also has a mother, Sachiko Yagami, and a younger sister, Sayu Yagami. In Spring 2004, Light becomes a first-year student (freshman) at To-Oh University (東応大学, Tōō Daigaku), becoming one of two freshman representatives; L is the other freshman representative. During a tennis game with L at To-Oh, spectators reveal that Light was the junior high school tennis champion in 1999 and 2000. After his 2000 victory, Light quit tennis as he entered high school. Yagami Light is a brilliant college student. Nicknamed "Kira," he uses the Death Note to create his ideal world of justice under him, its new God. Though he looks frail, Light is an extremely athletic person, with an aptitude to find an opponent's weak point. He is a genius, which adds to his notion that only he is fit to judge humanity and steer it on a proper moral course.