Shuki was a member of the Fu-Ma clan and the former head of the Fujibe faction, a combat faction dedicated to sealing demons.
He was the lover of Juju.
After Juju failed to return after a month from her mission to gather intelligence of Arahabaki's possible resurgence, a meeting was ordered by Chie. While Taki and the Inobe faction favored taking their time to research Arahabaki to better prepare themselves, Shuki grew angry at their inaction and chose to led his faction to Izumo without permission. This could have possibly been motivated by his relationship with Juju.
Tragically, he and the other faction members were killed by Juju, who had become possessed by Arahabaki. Taki was then forced to kill Juju.