Hobby Japan
A series of visual books, called , were published by Hobby Japan. The books are compilations of the illustrated stories posted on Hobby Japan's media site, Hobby Channel, along with additional material. The first visual book, written by Tomohiro Matsu and illustrated by Hagane Tsurugi and Eiwa, was released by Hobby Japan on September 26, 2009. A limited edition version of the book was also released on the same day, featuring a drama CD. The second visual book, called , written by Tomohiro Matsu and illustrated by Eiwa, was released by Hobby Japan on October 5, 2010. A third visual book, called , written by Eiji Okita and illustrated by Odanon and Eiwa, was released by Hobby Japan on July 28, 2012.