The official Twitter account of Ame-iro Cocoa (Rainy Cocoa) revealed on Monday that the short anime will receive a fifth season in 2019. An announcement video was released by the series' official YouTube channel, featuring Ryo Horikawa as the café owner Kouji Amami.
Ame-iro Cocoa has been published by IAM Comics since May 2013. The digital manga has received four short TV anime seasons by studio EMT² in Spring 2015, Fall 2015, Fall 2016, and Fall 2017; each running for 12 episodes. The first two seasons were simulcast by Funimation, who also shipped them on DVD in September 2016. Crunchyroll simulcast the fourth season and then later added all seasons to its catalogue.
The series follows the everyday occurrences at the Rainy Color café. Each season introduces a new set of main characters and connecting them with the returning ones, despite having a different focus on every story.
The original source, the voiced web manga that can switch in between Japanese and English, keeps the short anime going, I think, because the web manga official site says it's a big hit over 50+ countries.
I think few are watching because not much translation ver. available for anime and not many users understand just watching it without translation.