The creative team behind the “ISEKAI AFFAIR” manga series, writer Masakazu Ooi and artist Inomaru, are set to launch a new manga titled Ura Dungeon Oku-san (The Secret Dungeon Wife). The manga will debut in the next issue of Shogakukan’s Monthly Sunday GX magazine on April 18, 2025. Masakazu Ooi is credited with the original story, while Inomaru is illustrating the manga.
New Manga “Ura Dungeon Oku-san” Plot and Setting
“Ura Dungeon Oku-san” unfolds in a remote village where a mysterious “secret dungeon” suddenly appears after the defeat of the Demon King. This dungeon is filled with unimaginable monsters and incredible treasures. The story follows Yui, a newlywed who attempts to conquer this dungeon, while harboring a secret of her own.
Masakazu Ooi and Inomaru’s Previous Collaboration: ISEKAI AFFAIR Series
Prior to “Ura Dungeon Oku-san,” Masakazu Ooi and Inomaru collaborated on the ISEKAI AFFAIR: 10 Years After Defeating the Demon King, the Hero Cheats on His Wife With a Warrior Woman Who Lost Her Husband manga. This series launched on Shogakukan’s Sunday Webry website in December 2020, and its third and final compiled book volume was released in December 2021. Seven Seas Entertainment licensed the manga, releasing the first volume in English on January 7, 2025. The series is known for its mature themes and exploration of relationships in another world.
ISEKAI AFFAIR II: Guided Wives and Clumsy Otherworld Heroes Spinoff
The duo also created a spinoff manga titled ISEKAI AFFAIR II: Guided Wives and Clumsy Otherworld Heroes (Isekai Furin II – Michibikareshi Hitozuma-tachi to Bukiyō Tensei Yūsha). This spinoff launched in November 2021 on Shogakukan’s Sunday Webry website and concluded with its ninth and final volume on January 10, 2025.
About Masakazu Ooi
Masakazu Ooi is a prolific manga artist and writer. Born on March 4, 1975, in Kawasaki, Kanagawa Prefecture, Japan, Ooi has created numerous manga series across various genres, including:
- Oku-san: A long-running series serialized in Monthly Young King (later Young King OURs GH) from 2008 to 2024.
- Chii-chan no Oshinagaki: Another popular series by Ooi.
- Hero Girl x Healer Boy: Touch or Death: A series showcasing Ooi’s versatility.
Ooi is married to Yuuko Ootsuki (also known as Kanan), who is also a manga artist. His father-in-law is Yoshizawa Yasumi, making it a family of manga creators. Masakazu Ooi primarily works in the seinen genre, creating comedies and slice-of-life stories.
About Inomaru
Inomaru is a manga artist known for his work on the art for “ISEKAI AFFAIR”.
Inomaru’s Other Works
Besides his collaboration with Masakazu Ooi, Inomaru has also worked on other manga, including:
- Magicalize: Inomaru served as the artist for “Magicalize,” written by Tsunagami.
Where to Read Masakazu Ooi and Inomaru’s Manga
- ISEKAI AFFAIR: Available in English through Seven Seas Entertainment.
- Ura Dungeon Oku-san: To be serialized in Shogakukan’s Monthly Sunday GX magazine starting April 18, 2025.
