Based on a Japanese manga series by Osamu Takahashi. It was serialized in Kadokawa Shoten's magazine Young Ace from July 2009 to April 2017 and has been collected into nine tankobon volumes.
Episode 1 was previewed at a screening at Kadokawa Cinema Shinjuku in Tokyo on January 5, 2015. Regular broadcasting began on January 24, 2015.