Takanori Sewa, a wealthy Beika resident, serves as CEO of Sewa Financial Group. He occupies a large event-capable mansion staffed with servants. His elderly appearance features a bald head encircled by long grey hair and a prominent mustache. Sewa typically dresses in suits with bowties and maintains a relatively athletic build for his age. He presents a pleasant demeanor but harbors a strong attachment to his extravagant lifestyle and wealth, a financial motive driving his criminal actions. Sewa shares good terms with the wealthy Suzuki family, though Sonoko Suzuki notes her family's greater riches. His family includes a wife and a son. During the New Year's party in "The Great Detective Turned Small," Sewa hosts guests at his mansion. Tetsu Yamazaki, president of Yatsubishi Bank, is discovered murdered in a locked room, stabbed in the chest. Sewa fakes a leg injury requiring a wheelchair to establish an alibi. Shinichi Kudo investigates, deduces Sewa as the killer, and exposes evidence including a rope mechanism between windows and the absence of footprints, confirming an inside job. Sewa attempts flight but Shinichi subdues him using a thrown globe, leading to Sewa's arrest. His motive stems from financial disputes with Yamazaki. Following Sewa's conviction, his son inherits Sewa Financial Group. An alternate manga case depicts Sewa's wife murdered instead of Yamazaki, though the motive remains unspecified. Visible hair during the original anime crime scene suggests imperfect concealment. Sewa demonstrates an unexplained ability to handle firearms.