Kaori Katsuragi is Mikan's older sister being prepared to become the new head of the Katsuragi family.
Bayu or Tejas is a summoned demon.
I have no idea which is which; Bayu seems to be a reference to a river while Tejas seems to mean 'friend' or 'ally'.
Shinogi Minagi is the kannushi of a shrine who hires Astral to find her older brother.
Sakuya Isurugi attempted to take Nekoyashiki place during a ritual that ended badly.
