Icha Icha (イチャイチャ, English TV: Make Out) 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. 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.
- Icha Icha Paradise (イチャイチャパラダイス, Icha Icha Paradaisu, English TV: Make-Out Paradise) is the first in the series, written in three parts. Its plot is summarized 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 and 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.
- Icha Icha Violence (イチャイチャバイオレンス, Icha Icha Baiorensu, English TV: Make-Out Violence) 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.
- Icha Icha Innocence (イチャイチャイノセンス, Icha Icha Inosensu) 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.
- Icha Icha Tactics (イチャイチャタクティクス, Icha Icha Takutikusu, English TV: Make-Out Tactics) 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. 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: Family Day, Kakashi encourages Sasuke Uchiha to imitate scenes from Tactics to help him become closer with his daughter, Sarada. Sasuke calls Sarada his "cute peanut", a pet name used by one of the book's characters, but she takes this as a sign that he's forgotten her name. Sasuke then tries putting his cloak on her, which, in Tactics, instantly causes girls to fall in love, but Sasuke's cloak is too big for Sarada and she becomes so embarrassed that she storms off. Afterwards, Kakashi observes that the book's depictions may no longer be current due to its age, and so they wouldn't work on somebody of Sarada's age.
- On the cover page of Naruto chapter 531, Kakashi is holding a book titled Ero Ero Paradigm (エロエロパラダイム, Ero Ero Paradaimu).
- 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 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.
- In Boruto: Naruto Next Generations episode 127, Boruto Uzumaki, Sarada Uchiha, and Chōchō Akimichi try to get a copy of the book only for adults to interfere every time, insisting they're too young to read the book.