These stories typically follow 11-year-old Riley as she moves from the Midwest to San Francisco. The plot centers on her five personified emotions—Joy, Sadness, Anger, Fear, and Disgust—as they manage her experiences from "Headquarters".

The extension is a specific type of archive used for digital comics. Disney's Inside Out Cinestory - Amazon.com

The "Cinestory" format uses actual stills from the movie to create a graphic novel experience. Understanding the .cbz Format