The original novel, written by Natsumi Iwasaki with illustrations by Yukiusagi and Bamboo, was published by Diamondosha and released in Japan on December 4, 2009.

Shueisha compiled the series into three tankōbon volumes, released from May 2, 2011[5][6][7] In October 2010, the Japanese public broadcaster NHK announced that a 10-episode anime television series based on the novel would begin airing on its network starting in March 2011.

[8] Due to the 2011 Tōhoku earthquake and tsunami, the series was delayed from its original airdate and aired between April 25, 2011, and May 6, 2011, instead.

[9] Aimed at men and women in their 30s and 40s, the anime series is produced by Production I.G under the direction of Takayuki Hamana.

[10] A film adaption starring actress Atsuko Maeda as the lead role of Minami Kawashima was released in Japanese theatres on June 4, 2011.