Yen Press is releasing the manga in English and describes the story:
Welcome to Kowloon Walled City: a dystopian townscape where the people are brimming with nostalgia, and where the past, present, and future converge. Amid the hidden emotions and extraordinary daily lives of the men and women working in its confines, a tale of romance begins to unfold for real estate agent Reiko Kujirai―one that feels as familiar as Kowloon itself…
In November 2019, Mayuzuki started publishing their manga in Weekly Young Jump magazine from Shueisha. On Thursday, Shueisha will release the 11th volume of the compiled books. Yen Press already released the ninth volume on January 21st.
The anime version of the manga began airing on April 5th in Japan. Crunchyroll is currently streaming it simultaneously as it is being broadcasted in Japan.
This summer, a live-action movie adaptation of a popular manga series will be released. In the movie, Riho Yoshioka (Anime Supremacy!) portrays Reiko Kujirai, while Kōshi Mizukami (Nina, My Love) plays Hajima Kudō.
Mayuzuki's earlier work was After the Rain, a manga that started publishing in Monthly Big Comic Spirits from Shogakukan in 2014 before moving to Weekly Big Comic Spirits in early 2016. It released new chapters every other week until it concluded. ( link ) In April 2018, Shogakukan released the last volume of the manga. Vertical then acquired the rights for the series and put out all of it in five large collections.
In January 2018, the animated series based on the After the Rain manga began airing on Fuji TV's Noitamina block. It was accessible only on Amazon Prime Video both in Japan and globally. Additionally, a live-action film adaptation of the manga was released in Japan in May 2018.