an internet radio show promoting the anime entitled aired on onsen between december 27, 2007 and march 27, 2008. another radio show promoting the second anime called also aired on onsen between october 23, 2008 and april 23, 2009. the shows are hosted by misato fukuen and kimiko koyama, the voices of kurumu kurono and yukari sendo, respectively. a cd based on the first radio show was released by sony music entertainment on august 6, 2008, and another cd based on the second radio show was released on june 24, 2009.