Rainbow Days is a tV short anime that premiered in winter 2016, produced by Ashi Productions.

About the production: the story comes from a manga, there are 24 episodes of about 13 minutes and its current status is "finished".

Its main genres are comedy, romance and slice of life, with themes such as School, Shoujo, Male Protagonist and Primarily Teen Cast.

On AniList, Rainbow Days has an average score of 70%, a good score, and appears on 53,144 users' lists.

Nijiiro Days follows the colorful lives and romantic relationships of four high school boys—Natsuki Hashiba, a dreamer with delusions of love; Tomoya Matsunaga, a narcissistic playboy who has multiple girlfriends; Keiichi Katakura, a kinky sadist who always carries a whip; and Tsuyoshi Naoe, an otaku who has a cosplaying girlfriend. When his girlfriend unceremoniously dumps him on Christmas Eve, Natsuki breaks down in tears in the middle of the street and is offered tissues by a girl in a Santa Claus suit. He instantly falls in love with this girl, Anna Kobayakawa, who fortunately attends the same school as him. Natsuki's pursuit of Anna should have been simple and uneventful; however, much to his dismay, his nosy friends constantly meddle in his relationship, as they strive to succeed in their own endeavors of love. [Written by MAL Rewrite]

Official synopsis from AniList.