Nachi Sakuragi will reprise his role as Gai Amatsu/Kamen Rider Thouser in this spin-off. Written by Minato Takano (Kamen Rider Ex-Aid) and directed by Shojiro Nakazawa (Kamen Rider Ex-Aid: True Ending), the first episode of this spin-off will be included in the 1st Blu-ray box set, which is set for an April 8th release.
[Source: Dengeki Hobby via Daisuki Toku]