TV-Series
Description
Hajime Saitō serves as the captain of the Shinsengumi's 3rd Division. He is a native of Edo who stands approximately 169 centimeters tall and has a pale complexion. His appearance is marked by long indigo or black hair, which he typically wears tied in a loose side ponytail with bangs covering the right side of his face, and sharp blue eyes. His standard attire is a long, black fighting-style kimono worn with a simple white sash and a long scarf. Because he is left-handed, he wears his katana on his right hip to facilitate his unique drawing style. Later in the narrative, he changes into a black western-style outfit while retaining his sword.

Saitō is a man of few words who avoids conversation he deems meaningless, typically speaking only when spoken to or when he has something important to say. His manner of speaking is formal and almost entirely devoid of emotional display; he never shouts or shows visible anger. This stoic and reserved nature makes him appear cold and distant to others, but beneath this surface lies a thoughtful and perceptive individual who puts the safety of others above his own. He is extremely loyal to the Shinsengumi's vice-commander, Toshizō Hijikata, and will obey orders without question. Despite his formidable and intimidating presence, he possesses a shy and aloof side when it comes to personal matters, such as interacting with women or expressing his own feelings, a trait that occasionally makes him the subject of light teasing from his comrades. His loyalty extends to the Aizu domain, and he holds a deep, personal respect for Hijikata, who accepted him as a left-handed swordsman when others would not.

His background explains much of his quiet demeanor. As the first-born son of a prestigious samurai clan in Edo, he was unable to learn swordsmanship with his right hand due to his strong left-handedness, so he adopted a left-handed Iai style. This led to a duel with a fellow clansman; although Saitō won the match, he was accused of murder and subsequently exiled. After leaving his clan, he found his way to the Shieikan dojo, where he was befriended by other future Shinsengumi members including Sōji Okita, Shinpachi Nagakura, and Heisuke Toudou. It was there that he met Hijikata, whose respectful and kind gesture toward him, despite his unorthodox swordsmanship, inspired fierce and lasting loyalty.

In the story, Saitō is responsible for finding spies among the Shinsengumi ranks and carries out dangerous or morally complex missions. He is involved in a significant undercover operation where he pretends to leave the Shinsengumi and joins Itō Kashitarō's splinter group as a spy, gathering intelligence to prevent an assassination plot against commander Isami Kondō. During the Boshin War and the Shinsengumi's alliance with the Aizu Domain, he is assigned to train and lead Aizu warriors. Initially, these warriors reject him because of his western clothing and his left-handed fighting style, but his tactical decisions and devastating combat prowess during a siege earn him their deep respect and loyalty. In a key moment, he decides to remain with the Aizu forces after the Shinsengumi retreats, choosing to honor their loyalty rather than follow orders to leave them. He is last seen charging toward the enemy army, creating a diversion that allows the injured Hijikata and the remaining men to escape, an act that implies his presumed death in battle.

Saitō is considered one of the best swordsmen in the Shinsengumi. He is a master of Iaijutsu, a sword-based martial art focused on fluid movements that combine unsheathing and striking in a single motion, emphasizing a powerful, precise initial thrust. His left-handed technique makes him unpredictable in combat, as most opponents are accustomed to fighting right-handed swordsmen, providing him with a significant tactical advantage. This skill is so extraordinary that even his supernatural adversaries express respect for his abilities. He is known to wield his sword with incredible precision and control, capable of ending a fight with a single, decisive strike.