Millennium Family anime casts Mutsumi Tamura as Arthur
Millennium Family has cast Mutsumi Tamura as Arthur, the youngest Benfield sibling, but the anime still has no confirmed premiere date or overseas platform.
Millennium Family (踊る千年家族) has added Mutsumi Tamura to its cast as Arthur, the fifth son and youngest child of the Benfield family. The announcement appeared on the anime's official website on 10 November, alongside character artwork and a comment from Tamura.1
The new cast member
Arthur is presented as a boyish-looking character who is nevertheless calm, sharp-minded and capable of quietly solving problems within the family. The official profile also hints at a more mischievous side beneath his composed exterior, while describing him as someone who has lived for a very long time alongside his siblings.1
Tamura said Arthur's apparent youth contrasts with his long life and a special ability. She also described the character as affectionate but carrying many concealed feelings, suggesting that the role will have more going on beneath its surface than the character design initially implies.1
A growing ensemble
The official site previously listed Rikuya Yasuda as Theo, Lynn as Eve, Katsuyuki Konishi as Hayden, Haruna Mikawa as Raine, Taihi Kimura as Noel and Ryota Suzuki as Hugo. Arthur's addition completes another part of the Benfield family's central group, which follows seven immortal siblings.1
The production staff includes manga creator Sho Kasugai, director and series composer Masato Jinbo, character designer and chief animation director Hiroshi Yoneda, and animation studio PartsCraft. The anime is confirmed for TBS and other stations, but the official announcement has not given a specific premiere date or confirmed an international streaming platform.1
Our opinion
This is a useful casting update because Arthur's profile adds a distinct flavour to the family rather than simply expanding the roll call. The contrast between his childlike appearance, immense age and hidden ability gives the character an immediate hook, while Tamura's comments point towards a quieter emotional thread. The announcement remains deliberately light on broadcast timing, so the cast news is the story for now — not a release-date tease.
For viewers outside Japan, the practical caveat is that no overseas availability has been announced. Until the broadcasters or a streaming partner say otherwise, international fans will need to wait for confirmed distribution details rather than assume that a platform deal is in place.