After graduating from a university, Kaiu Shirai worked in a company that had no connection with the manga. Before The Promised Neverland was developed, he tried to create several stories, but all were rejected. He thought of giving up, telling himself that he had no talent like Mangaka, but ended up trying one last time, making a story called "Neverland," just to know if his story was good or bad, like the ones he had prepared before. Since he had not been able to summarize it, he ended up preparing 300 pages, a gigantic amount.
Takushi Sugita, the current editor of the series, was on the project with Kaiu, before Posuka Demizu entered. The editor was also responsible for joining the duo, testing them together with a One-Shot called Popy's Wish. According to him, "the two fell in love with each other." Posuka met with Kaiu, she read the entire script in one go. Posuka used to get rather bored while reading scripts, but she said that all 300 pages were so interesting that she could not stop.
Shirai fell in love with Posuka's artwork, just as Posuka fell in love with Shirai's writing. The author already knew the art of the designer before that and explained what he liked best in her art, and was very happy when she designed his one shot story, because the result was better than he expected.
At that time, Shirai was a complete stranger. So it was difficult to convince Jump to give the pair a chance, but Demizu relied on her partner's talent. From that time on, the author planned to let someone else draw, for even if he could draw alone, the editors felt that his drawings did not do justice to the plot he had prepared, and that he could not make a good series by taking care of both the script and the art. The Promised Neverland was not something planned for Weekly Shonen Jump, so it was difficult to decide together with the publisher which parties should stay and which ones should leave. Some parts of the story did not fit into Weekly Shonen Jump, but Shirai did not want to take them at all. When the one shot reception came out, being reasonably accepted, he was able to keep up with his vision.
|Title||Anthology||First Issue||Last Issue||Span|
|The Promised Neverland|
(約束のネバーランド, Yakusoku no Neverland)
|Weekly Shōnen Jump||Issue 35, 2016|
August 1, 2016
- Shirai loves movies and says they are a big influence on him. He says he likes a particular movie, a 1993 American film The Good Son.
- Coincidentally, one of the characters of the film is called Connie, a character of the same name appeared in the series.
- In the first page of Chapter 91, in Yugo's flashback, he was seen holding his dead friend Dina in his arms with a terrified look on his face―this is a reference to Ilya Repin's famous painting "Ivan the Terrible and His Son Ivan on November 16, 1581", or simply "Ivan the Terrible and His Son Ivan".
- In Issue 28 of Shounen Jump Manga, Shirai commented how he view the painting as "damaged" and loves it, inspired by the painting's expressiveness, he hence included the painting's pose into Chapter 91 of the Manga.
- Before The Promised Neverland, he made two One-Shots, a Popy's Wish (Popy in Negai in Japanese), to test how his relationship with Posuka would work, and the other Ashley: The Gate's Whereabouts, which he did with another artist.
- Kaiu Shirai likes to pass the message of Jump in his manga (Effort, Friendship and Victory) and, even with his story being something without battles and completely "Anti-Jump", he still hopes to get this message across.
- Shirai says he loves to deceive readers.
- Shirai says authors such as Naoki Urasawa (Works: Monster, Pluto, 20th Century Boys), Takeshi Obata (Works: Death Note, Bakuman, Hikaru no Go) and Yūsei Matsui (Works: Neuro: Supernatural Detective, Assassination Classroom) are some of his inspirations.
- In one of the special pages of the first volume of The Promised Neverland, Shirai stated the orphans' poorly drawn drawings that were pasted on the walls in the orphanage are drawn by him.