Determined to climb up the social ladder, Mary Saotome invests everything she has into what her elite high school values most: high stakes gambling.

The “Abyss” is the last unexplored region, an enormous and treacherous cave system filled with ancient relics and strange creatures. Only the bravest of adventurers can traverse its depths, earning them the nickname, “Cave Raiders.” Within the depths of the Abyss, a girl named Riko stumbles upon a robot who looks like a young boy. Tantalized by the Abyss, Riko and her new friend descend into uncharted territory to unlock its mysteries, but what lies in wait for them in the darkness?

Long ago, a war broke out in Japan that pitted Kantou against Kansai and divided the country. Kansai became dependent on Kantou, but slowly the police and government began losing control of Kansai to criminals known as Akudama.

Ladies versus Butlers! is a Japanese light novel series written by Tsukasa K?zuki, with accompanying illustrations by Muny?. The series includes 13 novels released between September 2006 and March 2012, published by ASCII Media Works under their Dengeki Bunko imprint. A manga adaptation by the illustrator group Nekoyashiki-Nekomaru was serialized in ASCII Media Works' Dengeki Moeoh magazine between the June 2008 and December 2008 issues. A drama CD based on the novels was released in September 2009. A 12-episode anime adaptation produced by Xebec and directed by Atsushi ?tsuki aired in Japan between January and March 2010. The anime has been licensed by Media Blasters for release in North America.