Why this use case is so distinct
A pet storybook is memorable because the subject is already emotionally loaded. The best versions do not just show a pet. They make the pet feel like the personality the whole story was built around.
This example works because Charlie is not just shown as a cute pet. The whole book treats his attitude, timing, and presence like the engine of the story.
Charlie did not simply arrive at the desk. Charlie made an entrance, paused for the room to react, and then settled in like a star who knew the cameras were already rolling.