CDs

The music for the series

 Is composed by Kōtarō Nakagawa and Hitomi Kuroishi, has been released across two original soundtracks produced by Yoshimoto Ishikawa and released by Victor Entertainment. The first was released in Japan on December 20, 2006, and the second on March 24, 2007. The covers and jackets for both soundtracks were illustrated by Takahiro Kimura.

The series has also been adapted into a series of drama CDs, called Sound Episodes, the first of which was released in Japan in April 2007 by Victor Entertainment, with new volumes released monthly. Written by many of the same writers as the series, these episodes are set between episodes and feature theme songs performed by the series' voice actors. They have also been available online on a limited streaming basis on the Japanese internet website Biglobe.^{[citation needed]}

In total, twelve drama CDs have been released. The first six, released between April 25, 2007 and September 27, 2007 cover the first season of the series, and the other six focusing on the second season.