Caucasus takes place in a small village named Nanatsuki Village (七月村 Nanatsuki Mura?) located in a remote, mountainous region. An old estate by the name of Nanatsu Mansion (七憑館 Nanatsu Kan?) is located there with a history of many strange and unexplained events having occurred there. These events are commonly referred to as being the "Curse of Nanatsuki" (七憑きの呪い Nanatsuki no Noroi?).
The story of Caucasus begins on a path to the Nanatsuki Village where a blizzard has stricken the two main characters. A young woman from the Nanatsu Mansion comes to their aid and provides them with shelter from the blizzard at the mansion. On that same day, a wedding was being held at the Nanatsuki Mansion. Meanwhile, the snowstorm continued to rage outside and in increasing severity.
The next day, the headless body of the groom was found which quickly sparked a dispute over the matter of assets and inheritance and whether this was another event caused by the "Curse of Nanatsuki". The suspension bridge outside had become frozen by the blizzard, cutting off the route to the outside world. What fate awaits the four men and seven women that remained at the Nanatsuki Mansion?
Internet radio show
An Internet radio show for promoting Caucasus, and the first Internet radio broadcast for Innocent Grey, aired its first broadcast on July 9, 2009. The show, produced by Rock'n' Banana, is hosted by Sanma Aji, who voices Venio Nanatsuki, and Doshizuku Hira, who voices Akane Hiyama, and is streamed online on every second and fourth Thursday of the month.
Caucasus will be the sixth project developed by Innocent Grey. It was announced on April 21, 2009 in the 2009 June issue of Tech Gian. Like their previous works, the concept art for Caucasus is being done by Miki Sugina.
The theme song to Caucasus, entitled "Snowdrop", was performed by Haruka Shimotsuki. The soundtrack of Caucasus was composed by Little Wing. Samples of the theme song and some background music tracks were provided with the 2009 September issue of Tech Gian. The soundtrack for the game was released on the same date as the game, on December 11, 2009.
- Official website (Japanese)