The upcoming TV anime adaptation of Kotobukiya’s “Kaijū Sekai Seifuku” (Monster World Conquest) project has unveiled new cast members and its theme song, along with confirming its April 5, 2025, TV debut. The anime, adapted from Hoshinoko’s four-panel manga, promises a heartwarming and surreal slice-of-life story about tiny monsters attempting world domination.
Plotting World Domination from an Apartment: The Premise of Kaijū Sekai Seifuku
The story of Kaijū Sekai Seifuku centers around four small, dragon-like monsters who arrive on Earth with grand plans of “world domination”. However, their ambitions take a backseat as they settle into a more relaxed routine. They reside in their master’s apartment, using it as their “secret base,” while spending their days learning about human culture and generally not conquering anything. The anime explores the chaotic yet heartwarming daily lives of these monsters as they navigate the human world, depicting them as gentle partners who offer a healing and comforting presence.
New Cast Members Announced
The anime’s official website released the names of the main cast members:
- Aoi Yūki voices the four kaijū: Mera, Gusuka, Aniki, and Sugar.
- Rina Kawaei plays the role of the kaijū’s owner, an OL (female office worker) in her 20s.
- Sōta Nakajima will voice a neighbor.
Production Staff
The production staff includes:
- Director: Kinuta Ōshiro
- Scriptwriter: Hiroto Naka
- Animation Studio: DLE
Theme Song
Details about the theme song were revealed, though the specific song title and artist were not explicitly mentioned in the search results.
A “Heartwarming Slice-of-Life”
Kaijū Sekai Seifuku is described as a “heartwarming slice-of-life” anime. The monsters, despite their initial goal of world conquest, end up freeloading off an office lady and turning her apartment into their base of operations. The four monsters each have distinct personalities:
- Mera: Spirited but scatterbrained.
- Gūsuka: An idle lazybones (a wordplay on the Japanese word for snoring).
- Aniki: Easily scared but reliable, acting as the “big brother” of the group.
- Sugar: Mischievous and gluttonous.
From Manga to Anime: A Brief History
Hoshinoko serialized a semimonthly four-panel manga of the Kaijū Sekai Seifuku project on Kadokawa’s Comic Newtype website from January 2020 to April 2021. Before the TV anime adaptation, a short anime series launched in April 2020 on Kotobukiya’s YouTube channel.