What is Kakashis book about?

You're likely referring to the "Make-Out Tactics" book that Kakashi Hatake carries. It's a humorous running gag in the Naruto universe, with the actual content of the book being shrouded in mystery.

Here's what we know:

* It's a guide on how to woo women. This is implied by the title and Kakashi's frequent use of the book, especially when trying to impress women.

* It's probably not very effective. Kakashi is often seen failing to use the book's "techniques" to his advantage, leading to hilarious situations.

* It's a source of amusement for his friends. Naruto, Sakura, and others poke fun at Kakashi's obsession with the book, further highlighting its comedic role.

The actual content of the book remains a secret, and the mystery adds to its charm. It's a playful element that reflects Kakashi's quirky personality and provides humor to the story.