Don Kanonji is a massively popular spirit medium whose television show, Ghost Bust, pulls in about 25% of Japan's entire viewership. He's known for his catchphrases—"Smells like bad spirits!" and "Spirits are always with you"—and his whole premise revolves around exorcising ghosts and sending them to the afterlife. Trouble is, his actual method of doing this accidentally transforms souls into hollows, something he remains completely oblivious to until Ichigo Kurosaki sets him straight. Grateful for the correction, Kanonji immediately makes Ichigo his "#1 Disciple."
After that wake-up call, Kanonji mostly shows up in omake chapters where things get a lot more tongue-in-cheek. Worried about his show's tanking ratings, he assembles the Karakura Superheroes—a ragtag team featuring the Kurosaki sisters and the kids from Urahara's shop—to fight hollows around town. Armed with his signature move, the Golden Kanonball (a slow-moving orb of golden light with a surprisingly powerful explosion), the group actually manages to keep the hollow problem under control.
He makes one significant reappearance during the Fake Karakura Town arc when Aizen corners Tatsuki and her friends. Kanonji is, predictably, useless in any real capacity—though he does eventually help them escape, but only after Rangiku yells at him and basically forces him into it.
Theme song: "L'Arlesienne Suite #2" by George Bizet
Content compiled by AnimeList.moe from publicly available sources.