Comic Flapper
Prior to writing "Twin Spica", Yaginuma had written several short stories depicting Asumi's childhood, beginning with . These stories were serialized by Media Factory from the July 2000 issue (released June 5, 2000) of the "seinen" manga magazine "Comic Flapper" until June 5, 2002. The Asumi story arc sets the stage for "Twin Spica" by introducing figures from her childhood that will affect her growth at the fictional Tokyo Space Academy. The main story arc at the space academy was first serialized in the October 2001 issue (released September 5, 2001) of "Comic Flapper". It continued until the publication of the 89th chapter on August 5, 2009. Both story arcs have been compiled into 16 bound volumes, with chapters of the Asumi story arc interspersed among several volumes. The series is licensed by Tong Li Publishing for Chinese-language release in Taiwan under the title "Dream of Spica" ().