Yamato Yura arrives at her new high school dormitory and makes friends right away - her cute roommate Sonora, and Sonora's friends Karila and Honoka. However, these girls all seem to have model air-guns, and, before Yura knows it, they've convinced her to join a club called C³ (C-cubed). Only after joining does she fully understand the meaning of "C-cubed": Command, Control, and Communication. C-cubed is a club for people who are into survival games! Will little Yura be able to live (and survive) with her new friends, the members of C³?