Icha Icha

is a series of adult novels written by Jiraiya after the commercial failure of The Tale of the Utterly Gutsy Shinobi. The Icha Icha novels are based on Jiraiya's experiences in love, particularly his rejections by Tsunade. When he's working on a new novel, he gathers "research" by peeping on women while they bathe. Teenagers are often curious about the books' contents, prompting their parents and other adults to go to great lengths to keep the books away from them.

Icha Icha is wildly popular, giving Jiraiya's checkbook a balance that is "filled with zeroes". Kakashi Hatake is a particular fan of the series; he enjoys reading the books even while in the middle of conversations. By the time of Kakashi Retsuden, Kakashi's picture and recommendation start to be printed on the books' cover.

Known Books

 * is the first in the series, written in three parts. Its plot is summarised as: "The main character and heroine, both new to love, begin dating, and their eyes gradually open to grown-up love." In Gaara Hiden, Gaara reads Paradise in an effort to learn more about relationships, but it only ends up making him more confused. Paradise eventually receives a film adaptation; in Konoha Shinden, it was filmed in a town in the Land of Fire, near the border with the Land of Hot Water. When Mirai Sarutobi asks Might Guy what the film is about, he becomes uncomfortable and abruptly changes the subject.
 * is the second book in the series. Ebisu enjoyed Violence more than Paradise, remarking that, "I have never seen the bonds between a man and a woman painted so stirringly." In Naruto episode 101, Violence also receives a film adaptation.
 * is the follow-up to Violence. When asked about it during an interview, Jiraiya says that he's still in the research phase of writing it, but that it will be about pure love.
 * is the first book to be published after a three year hiatus. Naruto Uzumaki gives Kakashi an advance copy, which he describes as "totally boring"; Jiraiya feels that Naruto is simply too young to appreciate it. In the anime, Tactics is split into several volumes, of which the fifth is so intense that readers tend to pass out by the end. For this reason, the fifth volume was removed after the first edition; Kakashi, who never read the first edition before, is convinced to help Yubeshi in exchange for a copy. Prior to his death, Jiraiya uses Tactics as the key for a secret message about Pain's identity. In order to decode the message, Kakashi is forced to read passages aloud; Kakashi is embarrassed to do so, and Shikamaru Nara is embarrassed to listen. In Naruto Shinden: Parent and Child Day, Kakashi encourages Sasuke Uchiha to imitate scenes from Tactics to help him become closer with his daughter, Sarada. Like the character in the book, Sasuke calls Sarada his "cute peanut" and tries putting his cloak on her as a sign of his love, but Sarada becomes so embarrassed that she storms off. Afterwards, Kakashi observes that the book wouldn't work on somebody Sarada's age since its depictions have become so out-of-date.

Trivia

 * On the cover page of Naruto chapter 531, Kakashi is holding a book titled.
 * In Naruto episode 177, Naruto ghost-writes an Icha Icha book in an attempt to force Jiraiya to train him. The manuscript is mistakenly sent to the Land of Fangs' daimyō as a peace treaty. The daimyō enjoys it so much that he ends his country's war with the Land of Claws.
 * In Boruto episode 37, Kakashi mentions he has Icha Icha Paradise memorised after reading the book for so many years.
 * In Boruto episode 127, Naruto is shown to have several copies of the entire series in his home's bookshelf, which Hinata took away when Boruto tried to read them.
 * In Naruto the Movie: Ninja Clash in the Land of Snow, Koyuki Kazahana is implied to star in the film adaptation of Icha Icha Paradise.
 * In Naruto: Ultimate Ninja 3, a copy of Icha Icha Strap can be gifted to Ebisu.
 * In Naruto SD: Rock Lee no Seishun Full-Power Ninden, there are at various times mentions of Icha Icha Pooltime, Icha Icha Emotion, Icha Icha Dynamic, and Ero Ero Install.