 In addition to the DVD and Blu-ray releases, all four seasons (excluding the Graduation arc) are streamed on Sentai's Anime Network website.The first season anime, along with the two-episode addition, used two pieces of theme music, one opening theme, and one ending theme.The opening theme is by Kana Asumi, Kaori Mizuhashi, Ryoko Shintani, and Yuko Goto; the single containing the opening theme was released on January 24, 2007.