日本一ソフトウェア
is a 2009 console role-playing game, co-developed by Nippon Ichi Software, Idea Factory and Gust Corporation exclusively for the PlayStation 3. The game is published by Idea Factory in Japan and NIS America in North America and Europe and was released in Japan on October 1, 2009 and in North America and Europe in June 2010. The game features characters from the "Atelier" and "Disgaea" series from Gust Corporation and Nippon Ichi Software respectively, with fully 3D character models for the first time.