An outrageous figure, Ganju dresses in a vest, scarf, bandana, and goggles. He is often seen with his gang, who ride large boars. His own boar is named Bonnie, affectionately referred to as Bonnie-chan. An omake sketch after episode 114 humorously suggests that Bonnie was accidentally cooked into a stew by Retsu Unohana during a friendly cookout. Despite this recurring joke, Bonnie always appears alive and well in subsequent episodes.
Ganju harbors a deep hatred for shinigami, has a fiery temper, and a strong ego. Although he acts tough, he shows a softer side, particularly when intimidated by his older sister Kūkaku. Over time, he develops an understanding with Ichigo Kurosaki, similar to Ichigo's relationship with Renji Abarai. A running joke in the series is Ganju's lack of attractiveness, which he tends to sidestep rather than deny, especially when Yumichika Ayasegawa points it out.
Ganju's grudge against shinigami stems from the death of his brother, Kaien Shiba, at the hands of Rukia Kuchiki when he was young. This resentment lingers even after learning the truth about the incident. Following Kaien and Miyako's deaths, the Shiba clan lost its status as one of the Noble Clans, leaving only four remaining noble families. Upon introduction, Ganju and Kūkaku are the last members of the Shiba clan.
Though not part of the shinigami forces, Ganju possesses combat skills surpassing those of an average shinigami but below higher-ranking officers. His zanpakutō resembles a meat cleaver or Chinese Dadao, though he never demonstrates its initial release. Due to limited sword skills, Ganju relies on his arsenal of fireworks, agility, and earth magic. His earth magic operates differently from standard shinigami kidō. The technique called Stone Wave (石波, seppa) does not require an incantation and can turn targets into sand or quicksand. This ability proved useful for making escape routes when fleeing from Yumichika.
