Born in Tokyo. Given name Shoichiro. Studied design, Japanese-style painting, and fabric dyeing. Brother-in-law Igusa Senshin was one of his teachers. Established a reputation in the 1920s as fabric designer for the Nozawaya department store in Yokohama. Became interested in hanga through Kawase Hasui. In 1930 took the art name Koitsu and devoted himself to prints. Published one set of prints of small-town or neighborhood genre scenes with Watanabe Shozaburo in 1931. Other works include Collection of Pictures of Toys (Omocha e shu), about 1935, and Hot Spring Landscapes (Onsen fukei), about 1940. Later works, sometimes combining woodblock and stencil, often published by Kato Junji.** Taken in whole, or in part, with permission from: Merritt, Helen and Nanako Yamada. Guide to Modern Japanese Woodblock Prints: 1900-1975. University of Hawaii Press: Honolulu. 1992.