The novel is written by Megumi Hatakenaka .
Kadokawa Shoten published novel on September 25 , 2007 ( ISBN 978 - 4 - 04 - 873786 - 9 ) .
The novel is written by Megumi Hatakenaka , and Kadokawa Shoten published it on September 25 , 2007 ( ISBN 978 - 4 - 04 - 873786 - 9 ) .