- This page is for the 2016 2-in-1 omnibus volume reprint. For the original volume 1, see The Case of Chiaki Yoshino.
The World's Greatest First Love: The Case of Chiaki Yoshino (世界一初恋 〜吉野千秋の場合〜, Sekai-ichi Hatsukoi: Yoshino Chiaki no Baai) is an omnibus light novel volume in the Sekai-ichi Hatsukoi series written by Fujisaki Miyako and Shungiku Nakamura. It reprints the contents from The Case of Chiaki Yoshino volume 1 and volume 2, with an additional chapter from volume 3.
The light novel has not been officially translated into English.
- The Case of Chiaki Yoshino No.1
- The Case of Chiaki Yoshino No.2
- The Case of Yoshiyuki Hatori No.1 ComicSide
- The Case of Chiaki Yoshino No.3
- The Case of Chiaki Yoshino No.4
- The Case of Chiaki Yoshino No.5
- The Case of Yoshiyuki Hatori No.2 ComicSide
- The Case of Yoshiyuki Hatori No.1
- The Case of Yuu Yanase No.1 ComicSide
"The Case of Yoshiyuki Hatori No.1 ComicSide" and "No.2 ComicSide" are the renamed manga chapters from the first two volumes. "The Case of Yoshiyuki Hatori No.1" is from volume 3.
"The Case of Chiaki Yoshino No.1" introduces Chiaki Yoshino, a mangaka of shoujo manga for Emerald magazine at Marukawa Publishing. His childhood friend Yoshiyuki Hatori is his editor, and his long-time friend Yuu Yanase is his manga assistant. Chiaki gets stressed when he begins to think that there's something between Yuu and Hatori, but then he falls ill and Hatori forces himself on Chiaki, causing more conflicted feelings. After days of avoiding the topic, Hatori confesses to Chiaki and tells him that someone else will be his editor, but Chiaki insists that Hatori not leave. With Chiaki resolving his own feelings, they begin a relationship.
In "The Case of Chiaki Yoshino No.2", Chiaki is still getting used to being intimate with Hatori and pushes him away. Tensions continue to rise with the annual Marukawa New Year's party. Chiaki attends the party with Yuu, and gets jealous seeing Hatori speak with the mangaka Erika Ichinose, so he and Yuu leave. Hatori visits Chiaki after the party to make up. When Yuu visits later, he indicates that there's someone he likes, leaving Chiaki guessing who it is.