He was voiced by Akira Ishida, who also voice Gaara from Naruto (Anime).
In his childhood, Katsura's parents died due to an illness , having been stripped off of their mansion, and he was left roaming the streets together with his grandmother. While visiting the grave of his parents, his grandmother taught him that no matter how strong or great a warrior may be, if he dies, he wouldn't be able to protect his country or any other people at all. So in order to be a great general, one must be more careful and more fearful in order to survive and lead the war.
In his childhood, Sakata Gintoki and Takasugi Shinsuke were Katsura's classmates under the same tutelage of Yoshida Shouyou. He made a resolve to be "a samurai who is both more cowardly and stronger than anyone else" so he could protect his comrades. After the Kansei Purge event, they would rise up as the last warriors of the Joui Patriots to free (and later, avenge) their beloved teacher from the Bakufu. Katsura later became comrades with Sakamoto Tatsuma during the Joui War.
When Katsura and Gintoki were injured, surrounded, and outnumbered by the Amanto, Katsura suggested that they should commit seppuku and die with honour, but Gintoki refused, saying they should rather live life out to the fullest with honour. Katsura agreed and they charged the enemies together.
After the Joui War, the three classmates went different paths as Katsura continued his activities fighting against the government.
During a Bakufu police force recruitment, Katsura was there, hiding in a shadow while hearing Matsudaira's proposal to protect their country from wrong hands, whether rules were followed or not.
He has long black hair (Okada Nizou wondered whether Katsura is really a man, for having such silky hair in Episode 58), He sports olive-brown eyes and has an attractive demeanor. He typically wears a blue kimono with a yellow sash. The fact that he typically wears a pale blue haori on top of his kimono and white socks with slippers suggests that he is particular about how he dresses and carries himself. He is never seen lying around or sitting in a unrefined manner, and he typically keeps his arms in his sleeves when not carrying anything. Since he is a wanted man, Katsura usually uses disguises to hide from Shinsengumi or to wander freely in public.