The "Colors" are three cute little girls who hang out together and say they're protecting the peace of their city. They have lots of fun together, doing stuff like playing games, solving puzzles, and going to the zoo. This anime follows their largely happy daily life.
https://myanimelist.net/anime/35078/Mitsuboshi_Colorsgotta start the year off with at least 1 Loli series, right?
happens to sound pretty cute too.