It was serialized in Shueisha's shōjo manga magazine Bessatsu Margaret from December 2011 to March 2017, with its chapters collected in sixteen tankōbon volumes.

Natsuki, the protagonist, is a hopeless romantic who has a crush on a girl named Anna who he met after his ex-girlfriend dumped him.

Written and illustrated by Minami Mizuno [ja], Rainbow Days was serialized in Shueisha's shōjo manga magazine Bessatsu Margaret from 13 December 2011[4] to 3 March 2017.

Tetsuro Amino served as chief director with Tomohiko Ohkudo directing at the animation studio Production Reed.

", was performed by Yoshitsugu Matsuoka, Takuya Eguchi, Nobunaga Shimazaki, and Kouki Uchiyama, the voice actors for Natsuki Hashiba, Tomoya Matsunaga, Keiichi Katakura, and Tsuyoshi Naoe, respectively.

[41] A live-action film adaptation directed by Ken Iizuka and distributed by Shochiku was released in Japanese theaters on 6 July 2018.