Yosuga no Sora is a visual novel game released on December 5, 2008 by Sphere (a sister brand of Cuffs), with artworks by Hashimoto Takashi and Hiro Suzuhira (whose last collaboration was on Pia Carrot 3), and the tagline "In solitude, where we are least alone". The game is Sphere's debut project, and on September 25, 2009 it received a fan disc called Haruka na Sora.