At the time of release, it was the first official coloring book for [Oshi no Ko] by Aka Akasaka and Mengo Yokoyari. It has 20 line drawings made from Mengo Yokoyari's illustrations for the manga, with main characters such as Ai of B-Komachi, Ruby Hoshino and Aqua Hoshino.
The first 8 pages are in color, and the pages from page 9 on are perforated so they can be cut out. The binding opens easily and is made to last.
The book has five extras: a large poster of Ai with her autograph on the back of the cover, mini color sample cards for every picture, a paper-craft case for the cards, idol fan-shaped memo cards, and a special message from Mengo Yokoyari.
Translated from the Japanese original.