It's common for a light novel to have a story being told from multiple perspective. But in Girlish Number, the story is being told from two different perspective where one of them is from Chitose's perspective and the other one is from Gojo's perspective.
Here's the thing about this book. There wasn't any distinction when the story is switching perspective. So, you will only be able to tell that a different perspective is taking place when you read the dialogue. That seems to be the only clue. And with so many chapter breaks, it can get confusing sometimes.
Another thing that I don't like about the book is the flow of Chitose's inner thought. It feels so jumbled up that I got myself lost as I try to figure out what's her point. Added with the Japanese term that may not be that familiar to the international audience make it even worst.
Of course, there's a little bit of explanation of all the Japanese term whether it's being explained in the story or in the separate section of the book. But I still find it confusing since I wasn't really that familiar with the term.
Despite the messy Chitose's perspective, I enjoy the story being told from Gojo's perspective since he delves deeper into the seiyuu industry that has yet to be covered in the anime like Sore ga Seiyuu! and Shirobako.
To be honest, I certainly don't consider the book to be badly written. But it's not that good either. I may give this book a higher rating if only I didn't get lost in trying to figure out what Chitose's main argument. Her mind is so jumbled up.