Kosaburo Katsura (桂 小三郎 Katsura Kosaburō?) is a private investigator in Digimon World Data Squad, a side-story to the main Digimon Data Squad universe. He is a civillian with a Digimon partner that acts outside the rules of DATS, making him something of a wild card in the story. His partner is a [[Biyomon ()|Biyomon]] who thinks very highly of Kosaburo's skills as a 'master detective'. It's implied that Kosaburo has interfered in some of DATS' missions in the past, particularly those of Yoshino "Yoshi" Fujieda, when his clients' requests are at odds with DATS' assigned missions. It is unknown how Kosaburo accesses the Digital World without DATS' Digital Dive technology.