This is a list of characters who appear in the Sekai-ichi Hatsukoi series.
Characters in this section work for Marukawa Publishing.
| Ritsu Onodera
Main character in the manga series The Case of Ritsu Onodera. Ritsu is hard working and wants to develop his skills as an editor. He has vowed to never be in love again, although he is currently developing a relationship with Masamune Takano.
| Masamune Takano
Main character in the manga series The Case of Ritsu Onodera. Editor-in-Chief of Emerald magazine. He is currently dating Ritsu Onodera.
| Shouta Kisa
Main character in the manga series The Case of Shouta Kisa. One of Marukawa's older editors. Due to his baby-face, he is mistaken to be younger than his real age. He is currently dating Kou Yukina.
| Yoshiyuki Hatori
Main character in the light novel series The Case of Chiaki Yoshino. Second editor-in-chief of Emerald magazine. He is currently dating mangaka and long-time friend Chiaki Yoshino.
| Kanade Mino
Supporting character. He often smiles, even in highly stressful situations, although Takano suggests never making him angry.
| Chiaki Yoshino (aka Chiharu Yoshikawa)
Main character in the light novel series The Case of Chiaki Yoshino. One of the most popular mangaka for Emerald, he works under a pen name so many think he is a woman. Only a few know he is male. He is currently dating Yoshiyuki Hatori.
| Yuu Yanase
Major supporting character in the light novel series The Case of Chiaki Yoshino. Chiaki's childhood friend. He is a mangaka assistant and is in love with Chiaki. Yuu knows about Hatori's feelings for Chiaki.
| Mutou Yukina
Supporting character. A well-known mangaka for Emerald magazine.
| Nanako Saitou
Minor character. A very popular mangaka for women.
| Erika Ichinose
Minor character. A star mangaka of Emerald magazine.
| Iori Satou
Minor character. A mangaka who does a last minute manuscript for Emerald.
Minor character. A mangaka for Emerald. Ritsu becomes her editor.
Other departments Edit
| Takafumi Yokozawa
Initially a supporting character in The Case of Ritsu Onodera, he becomes a main character in The Case of Takafumi Yokozawa. He works in the Sales Department and was in love with Takano until Takano makes it clear that he only has feelings for Ritsu. Yokozawa is currently dating Zen Kirishima.
| Zen Kirishima
A main character in The Case of Takafumi Yokozawa. Editor of Japun magazine at Marukawa. He is currently dating Takafumi Yokozawa.
| Ryuichiro Isaka
A supporting character. Isaka is Marukawa's Senior Managing Director. He's laid back and can be wishy-washy in meetings, to the frustration of the serious employees working under him. He features as a main character for one episode in the anime, in which he is in a relationship with Kaoru Asahina.
A minor character who works in printing. He gets stressed when manuscripts are late.
| Kazuma Henmi
Works in sales, a coworker of Takafumi Yokozawa.
| Yasuda Gou
A close friend and coworker of Zen Kirishima. He works in anime production.
| Kaoru Asahina
Ryuichiro Isaka's assistant.
| Sanae Hoshino
Works in printing. Hatori's ex-girlfriend from high-school.
| Akihiko Usami
A minor character who is a popular author. Ritsu Onodera used to edit his novels at Onodera Publishing, and some of his novels are published through Marukawa.
| Nao Kiyomiya
A supporting character in The Case of Ritsu Onodera. Former roommate of Ritsu when Ritsu studied abroad. He does not like Takano, believing Takano merely used Ritsu. He is a photographer and Marukawa is publishing a book of his photographs.
| Ryouichi Sumi
A supporting character in The Case of Ritsu Onodera. He is an author of novels, and Ritsu used to edit his novels at Onodera Publishing. Upon learning that Ritsu is now in manga editing, he suggests that Ritsu to return to literature.
A supporting character in The Case of Ritsu Onodera. He is a literature editor and edits Ryouichi Sumi's novels. When he meets Ritsu, he suggests that Ritsu could transfer to the literature editing department.
The main mascot of the Sekai-ichi Hatsukoi series and for Emerald magazine within the series.
Other professionals Edit
Marimo Books Edit
Characters in this section work for Marimo Books.
| Kou Yukina
A main character in The Case of Shouta Kisa. A T University student of art. He works at a bookstore and is a fan of the manga Kisa Shouta edits. Yukina is currently dating Shouta Kisa.
Characters in this section work for Shuudansha.
| Arata Haitani
A manga editor at Shuudansha. He and Takano previously worked together when Takano was still working at Shuudansha.
A former employee of Onodera Publishing who used to work with Ritsu. She and Ritsu remain friends. She currently works with Arata Haitani at Shuudansha.
Characters in this section work for Animate.
| Keiki Tezuka
Main character in The Case of Animate. He is in a relationship with Kensuke Saigusa.
| Kensuke Saigusa
Main character in The Case of Animate. He is in a relationship with Keiki Tezuka.
| Takuya Kusagawa
A minor character. He recognizes Yokozawa and Takano at the New Years Party and is introduced to Ritsu.
| An Kohinata
A supporting character in The Case of Ritsu Onodera. Ritsu's ex-fiancee, after Ritsu ended the engagement which was arranged by their parents. She remains a friend and is aware of Ritsu's relationship with Takano.
A man who Kisa has dated long before Kisa meet Yukina. Who doesn't give up on Kisa.
| Chinatsu Yoshino
Chiaki's younger sister. She has a crush on Hatori.
| Yoriko Yoshino
Mother of Chiaki and Chinatsu. Unaware of her son's relationship with Hatori, she wants Chiaki to find a girlfriend and start a family.
| Rio Kojima
One of Yukina's friends from the university. She may have feelings for Yukina.
| Hiyori Kirishima
Zen Kirishima's daughter.
A cat Masamune Takano found and adopted while in high school. Takafumi Yokozawa later adopted Sorata when Takano was having trouble, and he later gave the cat to Hiyori Kirishima.