That night, Haruaki is woken by a noise and is surprised to find a girl named Fear Kubrick in his kitchen eating rice crackers.

The story begins with high-school student Yachi Haruaki receiving a mysterious super-heavy black cube from his overseas archaeologist father.

That night, Haruaki wakes to a suspicious noise in the kitchen and discovers a stark-naked young girl with blue hair stealing rice crackers.

An anime television adaptation of C³ was announced in the April 2011 issue of ASCII Media Works's Dengeki AnimeStyle pamphlet.

[28] Tristan Crocker from Anime Herald gave a similar review, calling the story and characters underdeveloped, while at the same time deeming the show "a fun surprise".