The first stream was hosted on the personal YouTube channel of Shiho Kawaragi, who voiced the character in the games and TV anime series under the pseudonym Kaname Yuzuki.
He also runs a YouTube channel about Japan stuff called TheDoctorDazza, tweets at @DoctorDazza, and posts photos of his travels on Instagram.
Saionji’s model was borrowed from the original game creator 0verflow, who hosted the VTuber debut of Katsura in 2020.